Compiled by Carlos López C./Chemist
carlopez@matematicas.udea.edu.co

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Download full file  Full Agricola SPME 2000 - 2001

Record 1 of 187 in AGRICOLA 1998-2001/06

AU:  An,-M.; Haig,-T.; Hatfield,-P.
TI:  On-site field sampling and analysis of fragrance from living lavender (Lavandula angustifolia L.) flowers by solid-phase microextraction coupled to gas chromatography and ion-trap mass spectrometry.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. May 11, 2001. v. 917 (1/2) p. 245-250.
CN:  DNAL QD272.C4J68
LA:  English

Record 2 of 187 in AGRICOLA 1998-2001/06

AU:  Koziel,-J.A.; Noah,-J.; Pawliszyn,-J.
TI:  Field sampling and determination of formaldehyde in indoor air with solid-phase microextraction and on-fiber derivatization.
SO:  Environ-sci-technol. Washington, D.C. : American Chemical Society. Apr 1, 2001. v. 35 (7) p. 1481-1486.
CN:  DNAL TD420.A1E5
LA:  English

Record 3 of 187 in AGRICOLA 1998-2001/06

AU:  Eriksson,-M.; Dalhammar,-G.; Borg-Karlson,-A.K.
TI:  Biological degradation of selected hydrocarbons in an old PAH/creosote contaminated soil from a gas work site.
SO:  Appl-microbiol-biotechnol. Berlin, Germany : Springer Verlag. May 2000. v. 53 (5) p. 619-626.
CN:  DNAL QR1.E9
LA:  English
AB:  An old PAH/creosote contaminated soil (total approximately 300 microgram PAH/g soil) from a former gas work site in Stockholm, Sweden, has been treated at 20 degrees C with the addition of various nutrients and inoculated with bacteria (isolated from the soil) to enhance the degradation of selected hydrocarbons. Microcosm studies showed that the soil consisted of two contaminant fractions: one available, easily degraded fraction and a strongly sorbed, recalcitrant one. The bioavailable fraction, monitored by headspace solid phase microextraction, contained aromatics with up to three rings, and these were degraded within 20 days down to non-detectable levels (ng PAH/g soil) by both the indigenous bacteria and the externally inoculated samples. The nutrient additives were: a minimal medium (Bushnell-Haas), nitrate, nitrite, potting soil (Anglamark, Sweden), sterile water and aeration with Bushnell-Haas medium. After 30 days treatment most of the sorbed fractions were still present in the soil. Stirring or mechanical mixing of the soil slurries had the greatest effect on degradation, indicating that the substances were too strongly sorbed for the microorganisms. When stirring the choice of nutrient seemed less important. For the non-stirred samples the addition of nitrate with the bacterial inoculum showed the best degradation, compared to the other non-stirred samples. At the end of the experiments, accumulations of metabolites/degradation products, such as 9H-fluorenone, 4-hydroxy-9H-fluorenone, 9,10-phenanthrenedione and 4H-cyclopenta[def]phenanthrenone were detected. The metabolite 4-hydroxy-9H-fluorenone increased by several orders of magnitude during the biological treatments.
 Microbial activity in the soil was measured by oxygen consumption and carbon dioxide production.

Record 4 of 187 in AGRICOLA 1998-2001/06

AU:  Wang,-Z.; Hennion,-B.; Urruty,-L.; Montury,-M.
TI:  Solid-phase microextraction coupled with high performance liquid chromatography: a complementary technique to solid-phase microextraction-gas chromatography for the analysis of pesticide residues in strawberries.
SO:  Food-addit-contam. London ; Philadelphia : Taylor & Francis, c1984-. Nov 2000. v. 17 (11) p. 915-923.
CN:  DNAL TX553.A3F65
LA:  English

Record 5 of 187 in AGRICOLA 1998-2001/06

AU:  Baciocchi,-R.; Attina,-M.; Lombardi,-G.; Boni,-M.R.
TI:  Fast determination of phenols in contaminated soils.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Mar 9, 2001. v. 911 (1) p. 135-141.
CN:  DNAL QD272.C4J68
LA:  English

Record 6 of 187 in AGRICOLA 1998-2001/06

AU:  Eisert,-R.; Jackson,-S.; Krotzky,-A.
TI:  Application of on-site solid-phase microextraction in aquatic dissipation studies of profoxydim in rice.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Feb 9, 2001. v. 909 (1) p. 29-36.
CN:  DNAL QD272.C4J68
LA:  English

Record 7 of 187 in AGRICOLA 1998-2001/06

AU:  Tomkins,-B.A.; Sega,-G.A.; Ho,-C.H.
TI:  Determination of Lewisite oxide in soil using solid-phase microextraction followed by gas chromatography with flame photometric or mass spectrometric detection.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Feb 9, 2001. v. 909 (1) p. 13-28.
CN:  DNAL QD272.C4J68
LA:  English

Record 8 of 187 in AGRICOLA 1998-2001/06

AU:  Whiton,-R.S.; Zoecklein,-B.W.
TI:  Optimization of headspace solid-phase microextraction for analysis of wine aroma compounds.
SO:  Am-j-enol-vitic. Davis, Calif. : American Society for Enology and Viticulture. 2000. v. 51 (4) p. 379-382.
CN:  DNAL 390.9-Am33
LA:  English

Record 9 of 187 in AGRICOLA 1998-2001/06

AU:  Bellavia,-V.; Natangelo,-M.; Fanelli,-R.; Rotilio,-D.
TI:  Analysis of benzothiazole in Italian wines using headspace solid-phase microextraction and gas chromatography-mass spectrometry.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. Apr 2000. v. 48 (4) p. 1239-1242.
CN:  DNAL 381-J8223
LA:  English
AB:  Benzothiazoles are a part of the molecular structure of a large number of natural products, biocides, drugs, food flavors, and industrial chemicals. They also appear in the environment mainly as a result of their production and use as rubber vulcanization accelerators. A new headspace solid-phase microextraction (HS-SPME) method for analysis of benzothiazole (BTH) in wine is described. This method is fast, inexpensive, and does not require solvents. The detection limit of BTH in wine was 45 ppt with linearity up to 100 ppb. The quantification of BTH is performed by the standard additions method and does not require the use of an internal standard. We have analyzed 12 wines from different grape varieties grown in several regions, using SPME extraction and gas chromatography-mass spectrometry (GC-MS) detection. Under these experimental conditions, benzothiazole was found in all wines analyzed. Concentration levels in samples varied from 0.24 microgram/L (Vermentino) to 1.09 microgram/L (Franciacorta).

Record 10 of 187 in AGRICOLA 1998-2001/06

AU:  Elmore,-J.S.; Mottram,-D.S.; Hierro,-E.
TI:  Two-fibre solid-phase microextraction combined with gas chromatography-mass spectrometry for the analysis of volatile aroma compounds in cooked pork.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Jan 5, 2001. v. 905 (1/2) p. 233-240.
CN:  DNAL QD272.C4J68
LA:  English

Record 11 of 187 in AGRICOLA 1998-2001/06

AU:  Poerschmann,-J.; Gorecki,-T.; Kopinke,-F.D.
TI:  Sorption of very hydrophobic organic compounds onto poly(dimethylsiloxane) and dissolved humic organic matter. 1. Adsorption or partitioning of VHOC on PDMS-coated solid-phase microextraction fibers--a never-ending story.
SO:  Environ-sci-technol. Washington, D.C. : American Chemical Society. Sept 1, 2000. v. 34 (17) p. 3824-3830.
CN:  DNAL TD420.A1E5
LA:  English

Record 12 of 187 in AGRICOLA 1998-2001/06

AU:  Guidotti,-M.
TI:  Determination of Se4+ in drinkable water by solid-phase microextraction and gas chromatography/mass spectrometry.
SO:  J-AOAC-Int. Gaithersburg, MD : AOAC International. Sept/Oct 2000. v. 83 (5) p. 1082-1085.
CN:  DNAL S583.A7
LA:  English
AB:  A method was developed for the selective determination of Se4+ in drinkable water by solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS). Se4+ was selectively derivatized to ethane, 1,1'-selenobis by reaction with sodium tetraethylborate, extracted by the SPME fiber, and determined by GC/MS. Both headspace (HS)-SPME and direct SPME were studied. The method requires only a few milliliters of sample and 20 min for completion. At 2.0 microgram/L concentration, the relative standard deviation was 10.1% for HS-SPME and 9.1% for direct SPME. For HS-SPME, the theoretical detection limit was 81 ng/L and 166 ng/L for direct SPME. The recovery rate was 95%. The method was used to determine Se4+ in 10 tap water samples.

Record 13 of 187 in AGRICOLA 1998-2001/06

AU:  Paniandy,-J.C.; Chane-Ming,-J.; Pieribattesti,-J.C.
TI:  Chemical composition of the essential oil and headspace solid-phase microextraction of the guava fruit (Psidium guajava L.).
SO:  J-essent-oil-res. Carol Stream, Ill. : Allured Publishing Corporation. Mar/Apr 2000. v. 12 (2) p. 153-158.
CN:  DNAL SB298.J66
LA:  English
AB:  The oil and headspace of fresh white flesh guava fruits (Psidium guajava L.) from trees grown in Reunion island were obtained by steam hydrodistillation and headspace solid-phase microextraction (SPME), respectively. The chemical composition of the extract was investigated by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). A total of 73 compounds were identified, of which 61 by hydrodistillation and 24 by headspace SPME. In the headspace, the major constituents were: hexanal (65.9%), gamma-butyrolactone (7.6%), (E)-2-hexenal (7.4%), (E,E)-2,4-hexadienal (2.2%), (Z)-3-hexenal (2.0%), (Z)-2-hexenal (1.0%), (Z)-3-hexenyl acetate (1.3%) and phenol (1.6%), while beta-caryophyllene (24.1%), nerolidol (17.3%), 3-phenylpropyl acetate (5.3%) and caryophyllene oxide (5.1%) were the major volatile constituents present in the hydrodistilled oil. Many compounds were identified for the first time in the guava fruit such as gamma-butyrolactone (7.6%) in the headspace SPME and nerolidol (17.6%) in the oil. In addition some compounds such as (Z)-3-hexenal, (E,E)-2,4-hexadienal, gamma-butyrolactone, borneol, phenol, cuminyl alcohol could be identified only by the headspace method (SPME).

Record 14 of 187 in AGRICOLA 1998-2001/06

AU:  Mills,-G.A.; Walker,-V.
TI:  Headspace solid-phase microextraction procedures for gas chromatographic analysis of biological fluids and materials.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Dec 1, 2000. v. 902 (1) p. 267-287.
CN:  DNAL QD272.C4J68
LA:  English

Record 15 of 187 in AGRICOLA 1998-2001/06

AU:  Cremer,-D.R.; Eichner,-K.
TI:  Formation of volatile compounds during heating of spice paprika (Capsicum annuum) powder.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. June 2000. v. 48 (6) p. 2454-2460.
CN:  DNAL 381-J8223
LA:  English

Record 16 of 187 in AGRICOLA 1998-2001/06

AU:  Wu,-C.M.; Wang,-Z.; Wu,-Q.H.
TI:  Volatile compounds produced from monosodium glutamate in common food cooking.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. June 2000. v. 48 (6) p. 2438-2442.
CN:  DNAL 381-J8223
LA:  English

Record 17 of 187 in AGRICOLA 1998-2001/06

AU:  Roberts,-D.D.; Pollien,-P.; Milo,-C.
TI:  Solid-phase microextraction method development for headspace analysis of volatile flavor compounds.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. June 2000. v. 48 (6) p. 2430-2437.
CN:  DNAL 381-J8223
LA:  English

Record 18 of 187 in AGRICOLA 1998-2001/06

AU:  Jelen,-H.H.; Obuchowska,-M.; Zawirska-Wojtasiak,-R.; Wasowicz,-E.
TI:  Headspace solid-phase microextraction use for the characterization of volatile compounds in vegetable oils of different sensory quality.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. June 2000. v. 48 (6) p. 2360-2367.
CN:  DNAL 381-J8223
LA:  English

Record 19 of 187 in AGRICOLA 1998-2001/06

AU:  Ogihara,-H.; Horimoto,-Y.; Wang,-Z.H.; Skura,-B.J.; Nakai,-S.
TI:  Solid phase microextraction/gas chromatography of Salmonella-infected beef.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. June 2000. v. 48 (6) p. 2253-2259.
CN:  DNAL 381-J8223
LA:  English

Record 20 of 187 in AGRICOLA 1998-2001/06

AU:  Goupry,-S.; Rochut,-N.; Robins,-R.J.; Gentil,-E.
TI:  Evaluation of solid-phase microextraction for the isotopic analysis of volatile compounds produced during fermentation by lactic acid bacteria.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. June 2000. v. 48 (6) p. 2222-2227.
CN:  DNAL 381-J8223
LA:  English

Record 21 of 187 in AGRICOLA 1998-2001/06

AU:  Ebeler,-S.E.; Terrien,-M.B.; Butzke,-C.
TI:  Analysis of brandy aroma by solid-phase microextraction and liquid-liquid extraction.
SO:  J-sci-food-agric. West Sussex : John Wiley & Sons Limited. Apr 2000. v. 80 (5) p. 625-630.
CN:  DNAL 382-So12
LA:  English

Record 22 of 187 in AGRICOLA 1998-2001/06

AU:  Volante,-M.; Pontello,-M.; Valoti,-L.; Cattaneo,-M.; Bianchi,-M.; Colzani,-L.
TI:  Application of Solid Phase Micro-Extraction (SPME) to the analysis of pesticide residues in vegetables.
SO:  Pest-manag-sci. West Sussex, UK : Wiley, c2000-. July 2000. v. 56 (7) p. 618-636.
CN:  DNAL SB951-.P47
LA:  English

Record 23 of 187 in AGRICOLA 1998-2001/06

AU:  Lutzhoft,-H.C.H.; Vaes,-W.H.J.; Freidig,-A.P.; Halling-Sorensen,-B.; Hermens,-J.L.M.
TI:  Influence of pH and other modifying factors on the distribution behavior of 4-quinolones to solid phases and humic acids studied by "negligible-depletion" SPME--HPLC.
SO:  Environ-sci-technol. Washington, D.C. : American Chemical Society. Dec 1, 2000. v. 34 (23) p. 4989-4994.
CN:  DNAL TD420.A1E5
LA:  English

Record 24 of 187 in AGRICOLA 1998-2001/06

AU:  Gonzalez-Barreiro,-C.; Lores,-M.; Casais,-M.C.; Cela,-R.
TI:  Optimisation of alachlor solid-phase microextraction from water samples using experimental design.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Oct 27, 2000. v. 896 (1/2) p. 373-379.
CN:  DNAL QD272.C4J68
LA:  English

Record 25 of 187 in AGRICOLA 1998-2001/06

AU:  Fitzgerald,-G.; James,-K.J.; MacNamara,-K.; Stack,-M.A.
TI:  Characterisation of whiskeys using solid-phase microextraction with gas chromatography-mass spectrometry.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Oct 27, 2000. v. 896 (1/2) p. 351-359.
CN:  DNAL QD272.C4J68
LA:  English

Record 26 of 187 in AGRICOLA 1998-2001/06

AU:  Chen,-S.F.; Su,-Y.S.; Jen,-J.F.
TI:  Determination of aqueous chlorothalonil with solid-phase microextraction and gas chromatography.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Oct 27, 2000. v. 896 (1/2) p. 105-110.
CN:  DNAL QD272.C4J68
LA:  English

Record 27 of 187 in AGRICOLA 1998-2001/06

AU:  Hwang,-B.H.; Lee,-M.R.
TI:  Solid-phase microextraction for organochlorine pesticide residues analysis in Chinese herbal formulations.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Nov 17, 2000. v. 898 (2) p. 245-256.
CN:  DNAL QD272.C4J68
LA:  English

Record 28 of 187 in AGRICOLA 1998-2001/06

AU:  Wyllie,-S.G.; Fellman,-J.K.
TI:  Formation of volatile branched chain esters in bananas (Musa sapientum L.).
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. Aug 2000. v. 48 (8) p. 3493-3496.
CN:  DNAL 381-J8223
LA:  English
AB:  Substrates controlling the formation of branched chain volatile esters in ripening bananas were investigated by the application of alcohol and amino acid precursors to whole fruit and tissue samples. The resulting changes in the profile of the volatile esters were determined using SPME and GC. These changes revealed the selectivity characteristics of the esterification enzyme AAT, the availability of acyl CoA's for ester formation, and the role of substrate supply on volatile production. The results obtained suggest that substrate supply is a major determinant of the quantitative and qualitative composition of the resulting aroma profile.

Record 29 of 187 in AGRICOLA 1998-2001/06

AU:  Marsili,-R.T.
TI:  Shelf-life prediction of processed milk by solid-phase microextraction, mass spectrometry, and multivariate analysis.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. Aug 2000. v. 48 (8) p. 3470-3475.
CN:  DNAL 381-J8223
LA:  English
AB:  A technique based on solid-phase microextraction, mass spectrometry, and multivariate analysis (SPME-MS-MVA) was used to predict the shelf life of pasteurized and homogenized reduced-fat milk and whole-fat chocolate milk sampled over a 7 month period. Using SPME-MS-MVA, which is essentially a mass spectrometry-based electronic-nose instrument, volatile bacterial metabolites were extracted from milk with SPME (Carboxen-PDMS) and injected into a GC capillary column at elevated temperature. Mass fragmentation profiles from the unresolved milk volatile components were normalized to the intensity of a chlorobenzene internal standard mass peak (m/z 112) and subjected to MVA. Prediction models based on partial least-squares regression of mass intensity lists were able to predict the shelf life of samples to approximately +/-1 day, with correlation coefficients greater than 0.98 for the two types of milk samples. Using principal component analysis techniques, the procedure was also useful for classifying samples that were rendered unpalatable by nonmicrobial sources (contamination by copper and sanitizer) as well as by bacteria.

Record 30 of 187 in AGRICOLA 1998-2001/06

AU:  Lambropoulou,-D.A.; Konstantinou,-I.K.; Albanis,-T.A.
TI:  Determination of fungicides in natural waters using solid-phase microextraction and gas chromatography coupled with electron-capture and mass spectrometric detection.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Sept 29, 2000. v. 893 (1) p. 143-156.
CN:  DNAL QD272.C4J68
LA:  English

Record 31 of 187 in AGRICOLA 1998-2001/06

AU:  Brunton,-N.P.; Cronin,-D.A.; Monahan,-F.J.; Durcan,-R.
TI:  A comparison of solid-phase microextraction (SPME) fibres for measurement of hexanal and pentanal in cooked turkey.
SO:  Food-chem. Oxford : Elsevier Science Limited. Feb 2000. v. 68 (3) p. 339-345.
CN:  DNAL TX501.F6
LA:  English
AB:  Static headspace solid-phase microextraction (SPME) was evaluated for the quantitative measurement of hexanal in cooked turkey samples. Three fibre materials Carboxen/PDMS, PDMS/DVB and Carbowax/DVB with fibre thickness of 75, 65 and 65 micrometer, respectively, were compared for linearity, limit of detection, and repeatability of response to hexanal in cooked turkey samples. In terms of reproducibility and linearity of response the PDMS/DVB fibre was the most effective of the three fibres studied while Carboxen/PDMS was the most sensitive, with a limit of detention for hexanal of 2 ng/g. The use of 2-methyl pentanal as an internal standard facilitated the accurate measurement of hexanal and pentanal in oxidised turkey homogenates. In fresh and oxidised cooked turkey samples a high correlation between both hexanal and pentanal levels determined by SPME/GC and lipid oxidation measured as 2-thiobarbituric reactive substances (TBARS) was obtained.

Record 32 of 187 in AGRICOLA 1998-2001/06

AU:  Dittmann,-B.; Zimmermann,-B.; Engelen,-C.; Jany,-G.; Nitz,-S.
TI:  Use of the MS-sensor to discriminate between different dosages of garlic flavoring in tomato sauce.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. July 2000. v. 48 (7) p. 2887-2892.
CN:  DNAL 381-J8223
LA:  English
AB:  A method has been developed to discriminate between different dosages of garlic flavoring in tomato sauce with the help of a mass spectrometry based sensory system. Four fragment ions m/z 73, 81, 114, and 120 were selected as "sensor array" during  direct injection of the sample headspace into the mass spectrometer. Tomato sauces blended with different types of flavoring could be discriminated, and concentration gradients could be monitored. Fragment ions were chosen after volatile components had been analyzed and identified by SPME-GC/MS and HS-GC/MS (full scan). HS-GC/MS profiles of m/z 73, 81, 114, and 120 were recorded in the selected ion monitoring mode.

Record 33 of 187 in AGRICOLA 1998-2001/06

AU:  Hebert,-V.R.; Hoonhout,-C.; Miller,-G.C.
TI:  Reactivity of certain organophosphorus insecticides toward hydroxyl radicals at elevated air temperatures.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. May 2000. v. 48 (5) p. 1922-1928.
CN:  DNAL 381-J8223
LA:  English

Record 34 of 187 in AGRICOLA 1998-2001/06

AU:  Hebert,-V.R.; Hoonhout,-C.; Miller,-G.C.
TI:  Use of stable tracer studies to evaluate pesticide photolysis at elevated temperatures.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. May 2000. v. 48 (5) p. 1916-1921.
CN:  DNAL 381-J8223
LA:  English

Record 35 of 187 in AGRICOLA 1998-2001/06

AU:  Sabarez,-H.T.; Price,-W.E.; Korth,-J.
TI:  Volatile changes during dehydration of d'Agen prunes.
SO:  J-agric-food-chem. Washington, D.C. : American Chemical Society. May 2000. v. 48 (5) p. 1838-1842.
CN:  DNAL 381-J8223
LA:  English

Record 36 of 187 in AGRICOLA 1998-2001/06

AU:  Sampedro,-M.C.; Martin,-O.; Armentia,-C.L.-de.; Goicolea,-M.A.; Rodriguez,-E.; Balugera,-Z.G.-de.; Costa-Moreira,-J.; Barrio,-R.J.
TI:  Solid-phase microextraction for the determination of systemic and non-volatile pesticides in river water using gas chromatography with nitrogen-phosphorous and electron-capture detection.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Oct 6, 2000. v. 893 (2) p. 347-358.
CN:  DNAL QD272.C4J68
LA:  English

Record 37 of 187 in AGRICOLA 1998-2001/06

AU:  Bras,-I.; Santos,-L.; Alves,-A.
TI:  Monitoring organochlorine pesticides from landfill leachates by gas chromatography-electron-capture detection after solid-phase microextraction.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Sept 8, 2000. v. 891 (2) p. 305-311.
CN:  DNAL QD272.C4J68
LA:  English

Record 38 of 187 in AGRICOLA 1998-2001/06

AU:  Berrada,-H.; Font,-G.; Molto,-J.C.
TI:  Indirect analysis of urea herbicides from environmental water using solid-phase microextraction.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Aug 25, 2000. v. 890 (2) p. 303-312.
CN:  DNAL QD272.C4J68
LA:  English

Record 39 of 187 in AGRICOLA 1998-2001/06

AU:  Wirthensohn,-M.G.; Sedgley,-M.; Jones,-G.P.
TI:  Epicuticular wax of juvenile Eucalyptus leaves and headspace analysis of leaf volatiles.
SO:  J-essent-oil-res. Carol Stream, Ill. : Allured Publishing Corporation. July/Aug 2000. v. 12 (4) p. 401-411.
CN:  DNAL SB298.J66
LA:  English
AB:  This study was performed to determine the variation in leaf epicuticular wax composition and yield between 17 species of Eucalyptus with horticultural potential, and to identify a possible solvent for epicuticular wax using headspace volatile analysis. Variation in the amount and composition of leaf epicuticular wax among 17 species of Eucalyptus L'Heritier (Myrtaceae) with horticultural potential, was characterized by GC, TLC and GC/MS. Across species, wax yield ranged from 0.7 to 4.5 mg/cm2. The major wax constituents in all species except E. delegatensis R. Baker, were beta-diketones (24.7-83.0%), followed by wax esters (6.4-26.5%), n-alkanes (3.5-26.5%), fatty acids (3-15.9%), n-alcohols (0.6-11.1%) and aldehydes (0-9.2%). In E. delegatensis the major wax constituents were wax esters (46.6%), beta-diketones (24.7%), n-alkanes (11.5%), fatty acids (7.5%), n-alcohols (5.2%) and aldehydes (4.3%). Volatile organic compounds emitted from developing Eucalyptus leaves of six species were studied using solid phase microextraction (SPME), and were analyzed by GC and GC/MS. Leaf oils were extracted from four of the six species and the relative amounts of volatile compounds in the extract and headspace compared. The major volatile constituents were alpha-pinene (11.4-57.8%, headspace; 15.3-32.2%, oil extract) and 1,8-cineole (3.2-88.6%, headspace; 20.8-54.7%, oil extract). Other terpenoids present in the headspace in significant quantities were allo-aromadendrene, viridiflorene, alpha-thujene, alpha-phellandrene, gamma-terpinene and limonene. In the oil extract, allo-aromadendrene, alpha-phellandrene, viridiflorene and limonene were present in significant quantities. Components.
 of leaf oils are potential solvents involved in the transport of waxes from the epidermis to the cuticle, although this is not confined by the present study.

Record 40 of 187 in AGRICOLA 1998-2001/06

AU:  Liebig,-J.; Peeters,-C.; Oldham,-N.J.; Markstadter,-C.; Holldobler,-B.
TI:  Are variations in cuticular hydrocarbons of queens and workers a reliable signal of fertility in the ant Harpegnathos saltator.
SO:  Proc-Natl-Acad-Sci-U-S-A. Washington, D.C. : National Academy of Sciences,. Apr 11, 2000. v. 97 (8) p. 4124-4131.
CN:  DNAL 500-N21P
LA:  English
AB:  One of the key features of insect societies is the division of labor in reproduction between one or a few fertile individuals and many sterile nestmates that function as helpers. The behavioral and physiological mechanisms regulating reproduction in ant societies are still not very well understood, especially in species in which all colony members are reproductively totipotent. In the ponerine ant Harpegnathos saltator, queen-worker dimorphism is very limited, and a few mated workers reproduce ("gamergates") once the founding queen becomes senescent. Worker oviposition is regulated by highly directed aggressive interactions among nestmates, who can recognize different levels of ovarian activity. We show that variations in cuticular hydrocarbons (CHC) correlate with oogenesis, both for queens and workers. 13,23-Dimethylheptatriacontane is present in egg-layers, but not in infertile workers and  queens. Proportions of other CHCs vary as well, resulting in clear separation of the ants in a multivariate analysis. Egg-layers are characterized by an elongation of the chain length of CHCs. We used solid-phase microextraction to measure CHCs in live ants that were experimentally induced to start producing eggs. Over a period of 118 days, CHC profiles of infertile workers changed completely to that of reproductives. The effect of age can be excluded in this modification. This striking correlation of ovarian activity with CHC variation and its correspondence with the observed recognition behavior exhibited by the workers toward egg-laying nestmates suggests that CHCs serve as a fertility signal in the ant H. saltator, a reliable basis for regulating reproduction.

Record 41 of 187 in AGRICOLA 1998-2001/06

AU:  Mozuraitis,-R.; Buda,-V.; Jonusaite,-V.; Borg-Karlson,-A.K.; Noreika,-R.
TI:  Sex pheromones of Phyllonorycter acerifoliella and Ph. heegerella and communication peculiarities in three species of leafmining moths.
SO:  Entomol-exp-appl. Dordrecht : Kluwer Academic Publishers. Jan 2000. v. 94 (1) p. 15-23.
CN:  DNAL 421-En895
LA:  English
AB:  Females of the leaf miner moth Phyllonorycter acerifoliella (Z.) [=Ph. sylvella (Hw.)] and Ph. heegerella (Z.) (Lepidoptera: Gracillariidae: Lithocolletinae) release their sex pheromone at the beginning of photophase. The periodicity of the 'calling' behaviour of Ph. acerifoliella females was established. Three compounds from calling virgin Ph. heegerella females were collected by the Solid Phase Micro Extraction (SPME) technique and identified as (Z)-8-tetradecenyl acetate (Z8-14:OAc), tetradecyl acetate (14:OAc) and (Z)-8-tetradecenol (Z8-14:OH) in the ratio (88 +/- 3): (2 +/- 0.6) : (10 +/- 5) by capillary gas chromatography and mass spectrometry. Field trapping experiments demonstrated that the first two compounds are important for the attraction of conspecific males. Z814:OAc was found to be attractive when tested separately, while 14:OAc acted as synergist. The attractivity of the three component blend was reduced by 10% admixture of either (E)-10-dodecenyl acetate (E10-12:OAc) or (Z)-10-tetradecenyl acetate (Z10-14:OAc). Field tests of Z10-, Z8- and E10-14:OAc, identified from Ph. acerifoliella females, demonstrated that the first two compounds were essential for the attraction of conspecific males; so both are sex pheromone components. The attractivity of the three component bleed of Z10- Z8- and E10-14:OAc was reduced by 10% admixture of (E)10-dodecenol (E10-12:OH). The following four semiochemical compounds, Z8-14:OAc, Z8-14:OH, E10-14:OAc and 14:OAc, identified from phyllonoryctid females, as well as two sex attraction antagonists for Ph. acerifoliella and Ph. heegerella males, E10-12:OAc and Z10-14:OAc, are new for the family Gracillariidae. The results of field trapping.
 experiments revealed mechanisms ensuring the specificity of the chemocommunication systems in Ph. acerifoliella, Ph. heegerella and Ph. ulmifoliella (Hb) moths.

Record 42 of 187 in AGRICOLA 1998-2001/06

AU:  Zhou,-M.; Robards,-K.; Glennie-Holmes,-M.; Helliwell,-S.
TI:  Contribution of volatiles to the flavour of oatmeal.
SO:  J-sci-food-agric. West Sussex : John Wiley & Sons Limited. Jan 15, 2000. v. 80 (2) p. 247-254.
CN:  DNAL 382-So12
LA:  English
AB:  Flavour is of direct importance in the acceptance of oatmeals. Panel tests of an oatmeal sample require well-trained panellists and are expensive, time-consuming and difficult. To investigate an appropriate method of sensory testing to be used in a breeding programme, 12 oat samples were processed in the factory and their sensory qualities were assessed by a trained panel. Sensory quality was related to both variety and growing conditions, with variety being the major controlling factor. The volatile profile of the oatmeals was determined by solid phase microextraction using headspace and gas chromatography. Relatively few volatiles were detected in groats, while more than 50 peaks were detected in oatmeals, indicating that most of the volatiles in oatmeals were induced during heat processing. Volatile compounds detected from oatmeals were correlated with the sensory data, and chromatographic peak areas accounted for 43-94% of  the variations in sensory attributes. Preliminary identification of volatile compounds showed that the  major compounds included hydrocarbons, alcohols, acids and aldehydes.

Record 43 of 187 in AGRICOLA 1998-2001/06

AU:  Rochat,-D.; Ramirez-Lucas,-P.; Malosse,-C.; Aldana,-R.; Kakul,-T.; Morin,-J.P.
TI:  Role of solid-phase microextraction in the identification of highly volatile pheromones of two rhinoceros beetles Scapanes australis and Strategus aloeus (Coleoptera, Scarabaeidae, Dynastinae).
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. July 14, 2000. v. 885 (1/2) p. 433-444.
CN:  DNAL QD272.C4J68
LA:  English

Record 44 of 187 in AGRICOLA 1998-2001/06

AU:  Beltran,-J.; Lopez,-F.J.; Hernandez,-F.
TI:  Solid-phase microextraction in pesticide residue analysis.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. July 14, 2000. v. 885 (1/2) p. 389-404.
CN:  DNAL QD272.C4J68
LA:  English

Record 45 of 187 in AGRICOLA 1998-2001/06

AU:  Sala,-C.; Mestres,-M.; Marti,-M.P.; Busto,-O.; Guasch,-J.
TI:  Headspace solid-phase microextraction method for determining 3-alkyl-2-methoxypyrazines in musts by means of polydimethylsiloxane-divinylbenzene fibres.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. June 2, 2000. v. 880 (1/2) p. 93-99.
CN:  DNAL QD272.C4J68
LA:  English

Record 46 of 187 in AGRICOLA 1998-2001/06

AU:  Mestres,-M.; Marti,-M.P.; Busto,-O.; Guasch,-J.
TI:  Analysis of low-volatility organic sulphur compounds in wines by solid-phase microextraction and gas chromatography.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. June 9, 2000. v. 881 (1/2) p. 583-590.
CN:  DNAL QD272.C4J68
LA:  English

Record 47 of 187 in AGRICOLA 1998-2001/06

AU:  Kataoka,-H.; Lord,-H.L.; Pawliszyn,-J.
TI:  Applications of solid-phase microextraction in food analysis.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. June 2, 2000. v. 880 (1/2) p. 35-62.
CN:  DNAL QD272.C4J68
LA:  English

Record 48 of 187 in AGRICOLA 1998-2001/06

AU:  Mindrup,-R.F.
TI:  Recent applications of SPME for monitoring flavor components in foods.
SO:  Food-test-anal. Glendale, Calif. : Target Group, Inc. Feb/Mar 2000. v. 6 (1) p. 17-19.
CN:  DNAL TX541.F665
LA:  English

Record 49 of 187 in AGRICOLA 1998-2001/06

AU:  Betts,-T.J.
TI:  Solid phase microextraction of volatile constituents from individual fresh Eucalyptus leaves of three species.
SO:  Planta-med. Stuttgart : Georg Thieme Verlag,. Mar 2000. v. 66 (2) p. 183-195.
CN:  DNAL 450-P697
LA:  English

Record 50 of 187 in AGRICOLA 1998-2001/06

AU:  Zambonin,-C.G.; Palmisano,-F.
TI:  Determination of triazines in soil leachates by solid-phase microextraction coupled to gas chromatography-mass spectrometry.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Apr 7, 2000. v. 874 (2) p. 247-255.
CN:  DNAL QD272.C4J68
LA:  English

Record 51 of 187 in AGRICOLA 1998-2001/06

AU:  Hill,-P.G.; Smith,-R.M.
TI:  Determination of sulphur compounds in beer using headspace solid-phase microextraction and gas chromatographic analysis with pulsed flame photometric detection.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Mar 3, 2000. v. 872 (1/2) p. 203-213.
CN:  DNAL QD272.C4J68
LA:  English

Record 52 of 187 in AGRICOLA 1998-2001/06

AU:  Gou,-Y.; Eisert,-R.; Pawliszyn,-J.
TI:  Automated in-tube solid-phase microextraction-high-performance liquid chromatography for carbamate pesticide analysis.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Mar 17, 2000. v. 873 (1) p. 137-147.
CN:  DNAL QD272.C4J68
LA:  English

Record 53 of 187 in AGRICOLA 1998-2001/06

AU:  Augusto,-F.; Valente,-A.L.P.; Tada,-E.-dos-S.; Rivellino,-S.R.
TI:  Screening of Brazilian fruit aromas using solid-phase microextraction-gas chromatography-mass spectrometry.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Mar 17, 2000. v. 873 (1) p. 117-127.
CN:  DNAL QD272.C4J68
LA:  English

Record 54 of 187 in AGRICOLA 1998-2001/06

AU:  Page,-B.D.; Lacroix,-G.
TI:  Analysis of volatile contaminants in vegetables oils by headspace solid-phase microextraction with Carboxen-based fibres.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Mar 17, 2000. v. 873 (1) p. 79-94.
CN:  DNAL QD272.C4J68
LA:  English

Record 55 of 187 in AGRICOLA 1998-2001/06

AU:  Slege,-M.F.; Moneti,-G.; Pieraccini,-G.; Turillazzi,-S.
TI:  Use of solid-phase microextraction in the investigation of chemical communication in social wasps.
SO:  J-chromatogr-A. Amsterdam ; New York : Elsevier, 1993-. Mar 17, 2000. v. 873 (1) p. 73-77.
CN:  DNAL QD272.C4J68
LA:  English

Record 56 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Volatiles from duck feces attractive to Mexican fruit fly.
AU:  Robacker-DC; Garcia-JA; Bartelt-RJ
SO:  Journal-of-Chemical-Ecology. 2000, 26: 8, 1849-1867; 37 ref.
LA:  English
AB:  Aqueous extracts of three types of bird faeces were attractive to laboratory-colony Mexican fruit flies (Anastrepha ludens)in laboratory bioassays. Extracts of black-bellied whistling duck (Dendrocygna autumnalis) faeces were chosen for further analysis. Duck faeces extract was attractive to both sugar-fed and sugar-starved flies but was more attractive to sugar-fed flies. Protein deprivation of flies had no effect on their response. Duck faeces incubated in water for 24 h were more attractive than those incubated for longer periods. Duck faeces extract was attractive at pH 5-9, but was most attractive at pH 9, indicating that more than one class of chemicals contributed to attractiveness of the faeces. Major components of headspace of duck faeces extracts collected by solid-phase microextraction and identified by GC-MS, GC-FID, and GC-FTD included ethanol, propanol, phenol, ammonia, low-molecular weight amines, and pyrazines. In general, chemicals containing nitrogen proved most attractive to sugar-fed flies. However, dimethylamine and 1-pyrroline were nearly equally attractive to sugar-fed and sugar-deprived flies. Two chemicals without nitrogen were attractive to sugar-deprived flies; none were attractive to sugar-fed flies. A synthetic mixture was prepared containing ammonia, methylamine, dimethylamine, trimethylamine, 1-pyrroline, phenol, and 2-ethylhexanol in amounts found in odour of duck faeces extract. The synthetic mixture was 96% as attractive as duck faeces extract to sugar-fed flies and 80% as attractive to sugar-deprived flies.
PT:  Journal-article
AN:  20003000367

Record 57 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Solid-phase microextraction coupled with high performance liquid chromatography: a complementary technique to solid-phase microextraction-gas chromatography for the analysis of pesticide residues in strawberries.
AU:  Wang-Zhi; Hennion-B; Urruty-L; Montury-M; Wang-Z
SO:  Food-Additives-and-Contaminants. 2000, 17: 11, 915-923; 14 ref.
LA:  English
AB:  Solid-phase microextraction coupled with high performance liquid chromatography has been studied for the analysis of methiocarb, napropamide, fenoxycarb and bupirimate in strawberries. The strawberries were blended and centrifuged. Then, an aliquot of the resulting extracting solution was subjected to solid-phase microextraction (SPME) on a 60 µm polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibre for 45 min. at room temperature. The extracted pesticides on the SPME fibre were desorbed into SPME/high performance liquid chromatography (HPLC) interface for HPLC analysis with diode-array detection (DAD). The method is organic solvent-free for the whole extraction process and is simple and easy to manipulate. The detection limits were shown to be at low µg kg-1 level and the linear response covered the range from -0.05 to 2 mg kg-1 of pesticides in strawberries with a regression coefficient larger than 0.99. A good repeatability with RSDs between 2.92 and 9.25% was obtained, depending on compounds.
PT:  Journal-article
AN:  20003033549

Record 58 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Repeatability of pheromone blend composition in individual males of the southern green stink bug, Nezara viridula.
AU:  Miklas-N; Renou-M; Malosse-I; Malosse-C
SO:  Journal-of-Chemical-Ecology. 2000, 26: 11, 2473-2485; 18 ref.
LA:  English
AB:  The males of Nezara viridula (Heteroptera, Pentatomidae) produce a blend of four terpenoid compounds. The proportion of these four compounds varies among different populations. The terpenoid content of the volatile emission from individual males of a French population was monitored for several days with headspace solid-phase microextraction. The total amount of terpenoid compounds collected on an SPME fiber from one virgin male bug emitting over the course of 1 hr was very variable between samples. More than 50% of males released pheromone, at least during one part of the observation period. The relative percentages of bisabolene, nerolidol, trans-bisabolene epoxide, and cis-bisabolene epoxide were calculated and compared. The proportion of nerolidol in the blend showed a large dispersion between samples and a high coefficient of variation. The percentage values for bisabolene and its trans and cis epoxides were less dispersed, and the coefficients of variation for both epoxides were low. The proportion of trans epoxide relative to the two epoxides, which has been considered characteristic of pheromone strains of N. viridula, showed the smallest coefficient of variation. The repeatability index (RI) varied between 0.57 and 0.85 for the four compounds. Repeatability was particularly high for the two epoxide isomers. Stability in epoxide production was confirmed by statistical analysis (ANOVA), which revealed significant differences in the percentages of cis and trans epoxides between individuals. Correspondingly, the RI of the ratio of trans to cis + trans epoxides was over 0.8. Our study confirms the existence of an interindividual variation of the trans to cis epoxide ratio within populations of Nezara viridula but indicates that each individual reproducibly emits both isomers in the same proportion day after day.
PT:  Journal-article
AN:  20013008735

Record 59 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Screening for 2-acetyl-1-pyrroline in the headspace of rice using SPME/GC-MS.
AU:  Grimm-CC; Bergman-C; Delgado-JT; Bryant-R
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2001, 49: 1, 245-249; 9 ref.
LA:  English
AB:  Solid phase microextraction (SPME) is used to collect and concentrate the compounds in the headspace of rice. This research describes optimization parameters of temperature, moisture, and sampling time. Optimization was based upon the recovered levels of 2-acetyl-1-pyrroline (2-AP), the popcorn aroma in aromatic rice. The method uses a sampling temperature of 80 °C and adds 100 µL of water to a 0.75 g sample of rice. The rice was preheated for 25 min, a carboxen/DVB/PDMS SPME fiber was exposed to the headspace for 15 min, and a subsequent GC-MS analysis took 35 min. Samples of rice can be analysed as the flour, milled kernels, or brown rice. Twenty-one experimental rice varieties were analysed by the SPME method and compared to a wet technique. Recoveries of several nanograms of 2-AP from 0.75 g samples of aromatic rice were observed, whereas only trace amounts of 2-AP were recovered from nonaromatic rice. Recovery from a single SPME headspace analysis is calculated to be 0.3% of the total 2-AP in the sample.
PT:  Journal-article
AN:  20013018716

Record 60 of 187 in CAB Abstracts 2000/08-2001/07

TI:  The impact of a lignite seam on contaminated groundwater in the aquifer system of the Bitterfeld region.
AU:  Dermietzel-J; Christoph-G
SO:  Water,-Air,-and-Soil-Pollution. 2001, 125: 1-4, 157-170; 18 ref.
LA:  English
AB:  At the research area in Bitterfeld, Germany, highly mobile chlorinated aliphatics and aromatics have been detected in both groundwater and sediments, especially in a lignite seam. The modern analytical method of solid-phase micro extraction (SPME) was used to analyse the pollution level of groundwater and sediments. The lignite seam was found to have accumulated large quantities of halogenated hydrocarbons functioning as a giant adsorption filter, and hence recording past groundwater contamination. The vertical and lateral pollution profiles of sediments and the distribution coefficients between lignite and groundwater at equilibrium conditions were determined for the key components.
PT:  Journal-article
AN:  20013019384

Record 61 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Demonstration of 2-unsaturated C19-steroids in the urine of female Asian elephants, Elephas maximus, and their dependence on ovarian activity.
AU:  Dehnhard-M; Heistermann-M; Goritz-F; Hermes-R; Hildebrandt-T; Haber-H
SO:  Reproduction-Cambridge. 2001, 121: 3, 475-484; 50 ref.
LA:  English
AB:  An oestrous-related pheromone of the female Asian elephant (Elephas maximus) is known to induce behavioural responses in elephant bulls. Additional data revealed that timing of oestrus in females with close social relationships tends to be synchronized. Therefore, urine from female Asian elephants might be expected to contain luteal phase-dependent volatile substances, which may function as additional chemical signals in this species. The aim of the present study was to identify such compounds and to investigate their pattern of excretion throughout the ovarian cycle. Urine samples were collected 3 times a week during the follicular phase and 1 to 3 times a week during the luteal phase from 5 adult female Asian elephants from a total of 13 non-conception cycles and one conception cycle, including the first 72 weeks of pregnancy. A simple headspace solid-phase microextraction method has been developed for quantification of urinary volatile substances and analysis was performed by gas chromatography. The comparison of urine collected during the follicular and the luteal phase indicated the presence of two luteal phase-dependent substances. Mass spectrometry was used to identify one substance as 5alpha-androst-2-en-17-one and a second substance as the corresponding alcoholic compound 5alpha-androst-2-en-17beta-ol. The 5alpha-androst-2-en-17beta-ol and -17-one profiles reflected cyclic ovarian activity with clear (10-20-fold) luteal phase increases. Furthermore, measurements of both compounds were correlated positively with the concentration of urinary pregnanetriol and indicated cycle duration (15.1±1.2 weeks) similar to that obtained from pregnanetriol measurements (15.2±1.6 weeks). The results demonstrated the presence of 2 luteal phase-specific steroidal volatile compounds in elephant urine. One of the substances, 5alpha-androst-2-en-17-one, has been demonstrated in human axillary bacterial isolates. The measurement of both volatile substances in elephant urine can be used for rapid detection of the stage of the ovarian cycle, as the analysis can be completed within 2 h.
PT:  Journal-article
AN:  20013036216

Record 62 of 187 in CAB Abstracts 2000/08-2001/07

TI:  (Z)-dodec-3-en-1-ol, a novel termite trail pheromone identified after solid phase microextraction from Macrotermes annandalei.
AU:  Peppuy-A; Robert-A; Semon-E; Ginies-C; Lettere-M; Bonnard-O; Bordereau-C
SO:  Journal-of-Insect-Physiology. 2001, 47: 4-5, 445-453; 37 ref.
LA:  English
AB:  (Z)-dodec-3-en-1-ol was isolated and identified by GC-MS as the major component of the trail-following pheromone from whole body and sternal gland extracts of workers of the fungus-growing termite, Macrotermes annandalei (Silvestri) (Termitidae, Macrotermitinae). For the first time, this trail pheromone was also identified by using solid phase microextraction from the surface of the secretory sternal gland of workers. Bioassays showed that synthetic dodecenol induced both orientation and recruitment behavioral effects. The activity threshold of (Z)-dodec-3-en-1-ol in eliciting trail-following is similar to that of (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol in the Rhinotermitidae, but amounts of dodecenol secreted are 100 times higher than those of dodecatrienol. There is about 1 ng of (Z)-dodec-3-en-1-ol per worker. Artificial trails made of synthetic dodecenol are able to compete with natural trails in the field. The activity duration of synthetic (Z)-dodec-3-en-1-ol trails is shorter than that of trails made from whole sternal secretion of workers. Observations showed that (Z)-dodec-3-en-1-ol is probably the only major component of the trail-following pheromone of M. annandalei and that it could be associated with other compounds in a pheromonal blend providing specificity and/or stability to trails.
PT:  Journal-article
AN:  20013038149

Record 63 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Solid-phase microextraction-mass spectrometry: a new approach to the rapid characterization of cheeses.
AU:  Peres-C; Viallon-C; Berdague-JL
SO:  Analytical-Chemistry-Washington. 2001, 73: 5, 1030-1036; 24 ref.
LA:  English
AB:  This work describes a new method for the rapid characterization of cheeses by solid-phase microextraction coupled with mass spectrometry (SPME-MS). After four types of fibre were tested and the main extraction parameters studied, the volatile components were extracted using a Carboxen/PDMS 75-µm fibre placed for 10 minutes at 20°C in the headspace of the cheese. The substances adsorbed were then transferred directly from the injector to the inlet of a mass spectrometer through a 1-m deactivated silica capillary column heated to 210°C. The mass spectra thus obtained without prior chromatographic separation formed a "fingerprint" of the analyzed sample. For data analysis, the mass fragments of each spectrum (45 < m/z < 150 amu) were considered as potential descriptors of the composition of the headspace of the cheeses. Stepwise discriminant analysis was used to select a limited number of mass fragments that afforded an operational classification of the batches of cheeses studied. This new method offers the advantage of minimizing thermal, mechanical and chemical modifications of the matrix, thereby reducing the risk of analytical artifacts. SPME-MS provides a simple and effective approach to rapid quality control by analysis of the volatile fraction of foods. The discriminating power of the SPME-MS was evaluated using a range of 5 different cheeses of the Camembert type.
PT:  Journal-article
AN:  20013042673

Record 64 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Monoterpene biosynthesis in Agathosma crenulata (Buchu).
AU:  Fuchs-S; Sewenig-S; Mosandl-A
SO:  Flavour-and-Fragrance-Journal. 2001, 16: 2, 123-135; 20 ref.
LA:  English
AB:  Young plants of Agathosma crenulata [Barosma crenulata] were stem fed with aqueous solutions of 2H2 and 18O/2H2-labelled monoterpene ketone precursors. The essential oil was extracted by solid phase microextraction and subsequently analysed with enantioselective multidimensional gas chromatography--mass spectrometry. Both labelled pulegone precursors were converted into corresponding labelled menthone, isomenthone and menthofuran with different enantioselectivity. Feeding experiments with 18O/2H-labelled pulegone proved an enzymatic conversion of pulegone to menthofuran and the loss of the pulegone oxygen. Stereoselective analysis of all four isopulegone stereomers using octakis(2,3-di-OMICRON-butyryl-6-OMICRON-tert-butyldimethylsilyl )-gamma-cyclodextrin or heptakis(2,3-di-OMICRON-acetyl-6-OMICRON-tert-butyldimethylsilyl )-beta-cyclodextrin allowed the detection of enantiopure (1S)-cis- and (1S)-trans-isopulegone ( > 99%) in A. crenulata and buchu samples. Labelled isopulegone is discussed as a suitable pulegone precursor. Feeding experiments regarding the biosynthesis of 3-oxo-p-menthan-8-thiol and 3-oxo-p-menthan-8-thiol acetate are also reported.
PT:  Journal-article
AN:  20013044323

Record 65 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Flavor threshold for acetaldehyde in milk, chocolate milk, and spring water using solid phase microextraction gas chromatography for quantification.
AU:  Aardt-M-van; Duncan-SE; Bourne-D; Marcy-JE; Long-TE; Hackney-CR; Heisey-C; van-Aardt-M
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2001, 49: 3, 1377-1381; 22 ref.
LA:  English
AB:  The detection threshold of acetaldehyde was determined on whole, lowfat, and nonfat milks, chocolate-flavored milk, and spring water. Knowledge of the acetaldehyde threshold is important because acetaldehyde forms in milk during storage as a result of light oxidation. It is also a degradation product of poly(ethylene terephthalate) during melt processing, a relatively new packaging choice for milk and water. There was no significant difference in the acetaldehyde threshold in milk of various fat contents, with thresholds ranging from 3939 to 4040 ppb. Chocolate-flavored milk and spring water showed thresholds of 10048 and 167 ppb, respectively, which compares favourably with previous studies. Solid phase microextraction (SPME) was verified as an effective method for the recovery of acetaldehyde in all media with detection levels as low as 200 and 20 ppb in milk and water, respectively, when using a polydimethyl siloxane/Carboxen SPME fibre in static headspace at 45 °C for 15 min.
PT:  Journal-article
AN:  20013053354

Record 66 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Identification of volatile compounds in cantaloupe at various developmental stages using solid phase microextraction.
AU:  Beaulieu-JC; Grimm-CC
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2001, 49: 3, 1345-1352; 53 ref.
LA:  English
AB:  Using an automated rapid headspace solid phase microextraction (SPME) method for volatile extraction in cantaloupes, 86 compounds already reported for muskmelons were recovered and an additional 53 compounds not previously reported were identified or tentatively identified. The SPME method extracted a copious number of volatiles that can be analyzed to clearly differentiate between variety, growth stage, and stage of harvest ripeness. Most of the newly reported compounds in cantaloupe were esters and aldehydes that have already been demonstrated as flavor-related compounds in other products. All esters believed to have flavour impact increased progressively after pollination, and this trend continued with increasing harvest maturity. However, compound recovery often decreased when fruits were harvested over-ripe. Most aldehydes increased during early growth stages and then tapered off with increasing harvest maturity. The SPME method suitably recovered most compounds reported to impart characteristic flavor/aroma in muskmelons. SPME offers experimental flexibility and the ability to discover more compounds and address flavour quality changes in fresh-cut cantaloupe.
PT:  Journal-article
AN:  20013053454

Record 67 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Different stereoselectivity in the reduction of pulegone by Mentha species.
AU:  Fuchs-S; Beck-T; Mosandl-A
SO:  Planta-Medica. 2001, 67: 3, 260-262; 9 ref.
LA:  English
AB:  Aqueous solutions of [2H]-labelled pulegone enantiomers were fed to M. spicata subsp. spicata and M. spicata subsp. crispata shoot tip and first leaf pair. After solid phase microextraction, the essential oil was analysed with enantioselective multidimensional gas chromatography/mass spectrometry. But M. spicata species were able to convert labelled (1R)- and (1S)-pulegone at the same rate into the corresponding menthone and isomenthone, indicating an unspecific process. The reduction of both pulegone enantiomers preferably led to the cis stereoisomers. The observed stereoselectivity is completely different from those of pulegone reduction by Mentha x piperita.
PT:  Journal-article
AN:  20013055584

Record 68 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Formation of allyl isothiocyanate from sinigrin in the digestive tract of rats monoassociated with a human colonic strain of Bacteroides thetaiotaomicron.
AU:  Elfoul-L; Rabot-S; Nasser-Khelifa; Quinsac-A; Duguay-A; Rimbault-A
SO:  FEMS-Microbiology-Letters. 2001, 197: 1, 99-103; 23 ref.
LA:  English
AB:  A human digestive strain of B. thetaiotaomicron was tested for its ability to metabolize sinigrin, a glucosinolate commonly found in Brassica vegetables. Gnotobiotic rats harbouring the bacterial strain were orally treated with 50 µmol sinigrin. HPLC analysis of the digestive contents showed that sinigrin was degraded in the large bowel, where B. thetaiotaomicron was established at a high level. Concurrently, a hydrolysis product of sinigrin, allyl isothiocyanate, was identified by GC-MS analysis, following headspace solid-phase microextraction of the digestive contents; its production peaked at ca. 200 nmol, 12 h after treatment. This is thought to be the first study to demonstrate in vivo the involvement of a human colonic predominant bacterium in the bioconversion of a dietary glucosinolate to a potentially anticarcinogenic isothiocyanate.
PT:  Journal-article
AN:  20013057807

Record 69 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Solid-phase microextraction for the enantiomeric analysis of flavors in beverages.
AU:  Ebeler-SE; Sun-GM; Datta-M; Stremple-P; Vickers-AK
SO:  Journal-of-AOAC-International. 2001, 84: 2, 479-485; 22 ref.
LA:  English
AB:  Solid-phase microextraction combined with gas chromatographic/mass spectrometric analysis and separation on a chiral cyclodextrin stationary phase was a rapid, reliable technique for profiling chiral aroma compounds in flavoured alcoholic beverages. Several enantiomeric terpenes, esters, alcohols, norisoprenoids, and lactones were identified in berry-, peach-, strawberry-, and citrus-flavoured wine and malt beverages (wine coolers). Using this technique, we were able to confirm the addition of synthetic flavouring to several beverages, consistent with label designations.
PT:  Journal-article
AN:  20013059444

Record 70 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Comparison of polyphenols and aroma in red wines from Portuguese mainland versus Azores Islands.
AU:  Baptista-JAB; Tavares-JF-da-P; Carvalho-RCB; da-P-Tavares-JF
SO:  Food-Research-International. 2001, 34: 4, 345-355; 34 ref.
LA:  English
AB:  trans-Resveratrol (trans-3,5,4'.trihydroxystilbene), piceid (resveratrol 3-O-beta-D-glucopyranoside), together with their isomers and quercetin were measured in red wines from cultivars grown in Portuguese mainland and Azores Islands. Crude hydroxystilbenes and quercetin were extracted by solid-phase extraction-C18 cartridges, and eluted with ethyl acetate. Recoveries of added trans-resveratrol and quercetin were between 90.2 to 101% (mean 96.8%) and between 95.2 and 97.6% (mean 96.2%), respectively. The precision measured by coefficients of variation (overall mean) ranged from 1.8 to 3.3%, and the calibration curves were linear with the mean correlation coefficients of 0.9997 and 0.9978 for trans-resveratrol and quercetin, respectively. The wine polyphenolic compounds were separated by reverse-phase C18 HPLC column and identified by UV fast scanning, retention times and HPLC/MS. The average content of total stilbenes was 4.75 and 6.33 mg/l, that of quercetin was 4.38 and 5.57 mg/l, and the trans/cis ratio was 8.32 and 10.89 for piceid and 5.2 and 4.09 for resveratrol in Portuguese mainland and Azorean wines, respectively. The Azorean wine (Basalto) was notable in having the highest trans-resveratrol concentration. The aroma profile of red wine samples from different regions were compared using SPME/GC-MS headspace methodology.
PT:  Journal-article
AN:  20013060123

Record 71 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Limitations to the use of solid-phase microextraction for quantitation of mixtures of volatile organic sulfur compounds.
AU:  Murray-RA
SO:  Analytical-Chemistry-Washington. 2001, 73: 7, 1646-1649; 16 ref.
LA:  English
AB:  A study of the range of volatile organic sulfur compounds produced by Brassica plants have highlighted limitations to the use of Carboxen/PDMS fibres for their analysis by solid-phase microextraction (SPME). These fibres were sometimes advocated for the analysis of sulfur gases, but a quantitative comparison of analytical data derived by SPME and by direct gas sampling of standard mixtures of volatile low molecular weight sulfur compounds at 0.01-10 mg/litre have identified potential errors associated with their use. Higher molecular compounds displaced lower molecular weight compounds as a consequence of competition for active sites on the fibre, and the relative proportions of the components adsorbed onto the fibre depended on their ratio in the headspace. As their relative concentrations changed from sample to sample, the varying interactions resulted in irregular analytical responses, reflected in erratic calibration curves. Standards containing single components were not valid; only the standard containing all components found in the sample to be analysed, and at the same relative concentrations, were appropriate. In practice, this may preclude the use of the fibres for quantitative analysis of multicomponent mixtures.
PT:  Journal-article
AN:  20013061392

Record 72 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Development of a SPME-GC-ECD methodology for selected pesticides in must and wine samples.
AU:  Correia-M; Delerue-Matos-C; Alves-A; Camoes-MF
SO:  Euroanalysis XI. Proceedings of the European Conference on Analytical Chemistry, Lisbon, Portugal, 3-8 September 2000. Fresenius'-Journal-of-Analytical-Chemistry. 2001, 369: 7-8, 647-651; 11 ref.
LA:  English
AB:  A method for the determination of some pesticide residues in must and wine samples was developed using solid-phase microextraction and gas chromatography-electron capture detection. The procedure only needs dilution as sample pre-treatment and is therefore simple, fast and solvent-free. Eight fungicides (vinclozolin, procymidone, iprodione, penconazole, fenarimol, folpet, nuarimol and hexaconazole), one insecticide (chlorpyriphos [chlorpyrifos]) and two acaricides (bromopropylate and tetradifon) can be quantified. Good linearity was observed for all the compounds in the range 5-100 µg/l. The reproducibility of the measurements was found acceptable (with RSD below 20%). Detection limits of 11 µg/l, on average, are sufficiently below the proposed maximum residue limits for these compounds in wine. The analytical method was applied to the determination of these compounds in Portuguese must and wine samples from the Demarcated Region of Alentejo, where any residues could be detected.
PT:  Journal-article; Conference-paper
AN:  20013068500

Record 73 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Rapid methods in plant aroma analysis -- mass spectrometric sensor measurements on strawberries.
AU:  Ulrich-D; Hoberg-E; Geibel-M (ed.); Fischer-M (ed.); Fischer-C
SO:  Proceedings of the EUCARPIA Symposium on Fruit Breeding and Genetics, volume 2, Dresden, Germany, 6-10 September, 1999. Acta-Horticulturae. 2000, No. 538 (Vol.2), 443-446; 3 ref.
LA:  English
AB:  The purpose of this paper is to discuss the specific features of flavour analysis methods in plant breeding and breeding research with strawberry as an example. It is possible to create genotypes with highly variable aroma patterns by crossing varieties. To support the selection of high numbers of progenies with positive aroma properties, rapid flavour analysis methods are recommended. As an example of such methods the combination of head-space SPME with a mass spectrometric sensor was tested.
PT:  Journal-article; Conference-paper
IB:  90-6605-903-6
AN:  20003032330

Record 74 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Automated in-tube solid phase microextraction coupled with HPLC-ES-MS for the determination of catechins and caffeine in tea.
AU:  Wu-JingCun; Xie-Wei; Pawliszyn-J; Wu-JC; Xie-W
SO:  Analyst. 2000, 125: 12, 2216-2222; 40 ref.
LA:  English
AB:  A polypyrrole (PPY) coated capillary and several commercially available capillaries (capillary GC columns) were used to evaluate their extraction efficiencies for catechins and caffeine. Compared with commercial capillaries that were currently used for in-tube solid phase microextraction (SPME), the PPY coated capillary showed better extraction efficiency for all of the compounds studied. Electrospray mass spectrometric (ES-MS) detection conditions were also investigated. After optimization of the extraction and detection conditions, a method for the sensitive and selective determination of catechins and caffeine was developed by coupling the PPY coated capillary in-tube SPME with HPLC-ES-MS. Catechins could be determined in both positive and negative ion detection modes. The detection limit (S/N=3) for each of the studied catechins was < 0.5 ng mL-1. Caffeine could only be determined under positive ES-MS detection conditions and its detection limit was 0.01 ng mL-1. Caffeine and the five catechins in several tea samples were determined using the developed method. Small amounts of catechins were also detected in grape juice and wine samples.
PT:  Journal-article
AN:  20013000430

Record 75 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Sampling and analysis of airborne particulate matter and aerosols using in-needle trap and SPME fiber devices.
AU:  Koziel-JA; Odziemkowski-M; Pawliszyn-J
SO:  Analytical-Chemistry-Washington. 2001, 73: 1, 47-54; 30 ref.
LA:  English
AB:  A needle trap device (NTD) and commercial poly(dimethylsiloxane) (PDMS) 7-µm film thickness solid-phase microextraction (SPME) fibres were used for the sampling and analysis of aerosols and airborne particulate matter (PM) from an inhaler-administered drug, spray insect repellent, and exhaust diesel exhaust. The NTD consisted of a 0.53-mm o.d. stainless steel needle having 5 mm of quartz wool packing section near the needle tip. Samples were collected by drawing air across the NTD with a Luertip syringe or via direct exposure of the SPME fibre. The mass loading of PM was varied by adjusting the volume of air pulled through the NTD or by varying the sampling time for the SPME fibre. The air volumes ranged from 0.1 to 50 ml, and sampling times varied from 10 s to 16 min. Particulates were either trapped on the needle packing or sorbed onto the SPME fibre. The devices were introduced to a chromatograph/mass spectrometer (GC/MS) injector for 5 min desorption. In the case of the NTD, 10 µL of clean air was delivered by a gas-tight syringe to aid the introduction of desorbed analytes. The compounds sorbed onto particles extracted by the SPME fibre or trapped in the needle device were desorbed in the injector and no carry-over was observed. Both devices performed well in extracting airborne polycyclic aromatic hydrocarbons (PAHs) in diesel exhaust, triamcinolone acetonide in a dose of asthma drug and DEET in a dose of insect repellent spray. Results suggest that the NTDs and PDMS 7-µm fibres can be used for airborne particulate sampling and analysis, providing a simple, fast, reusable, and cost-effective screening tool. The advantage of the SPME fibre is the open-bed geometry allowing spectroscopic investigations of particulates; for example, with Raman microspectroscopy.
PT:  Journal-article
AN:  20013011807

Record 76 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Emission of volatiles from brown boronia flowers: some comparative observations.
AU:  MacTavish-HS; Davies-NW; Menary-RC
SO:  Annals-of-Botany. 2000, 86: 2, 347-354; 36 ref.
LA:  English
AB:  Volatiles emitted from flowers of Boronia megastigma were trapped by solid phase microextraction, and compared for their presence in dissected floral parts; in buds and flowers at different stages of development; and in the whole flower during exposure of plants for 36 h to continuous light, continuous dark and 12 h light:12 h dark:12 h light treatments. In buds, volatiles were emitted up to a month prior to flower opening. Caryophyllene, humulene, and bicyclogermacrene dominated the headspace at this time but their proportion subsequently declined. Open flowers emitted the greatest amount of volatiles. During senescence, only alpha-pinene, caryophyllene, bicyclogermacrene, dodecyl acetate and (Z)-n-heptadec-8-ene were emitted and total volatile emission was reduced. Most volatiles emanated from the petaline anthers (37.6% of the calculated emission of the flower) and petals (26.7%). The greatest amounts of monoterpene (alpha- and beta-pinene, camphene, myrcene, limonene and cisbeta-ocimene) emissions were from the calyx (which included the nectary tissue beneath the stigma). beta-Ionone comprised 30% of emitted volatiles from the calyx/nectary and 87.2% from the stigma. Nine of the 23 volatiles emanated by flowers from plants subjected to different light environments were identified and these showed 3 different emission patterns: (a) emission greatest in the endogenous dark period, regardless of light environment (alpha-pinene); (b) emission similar in all treatments with an increase and decline in emission over a period of 26 h (5-acetoxylinalool, cyclic beta-ionone, dodecyl acetate and (Z)-n-heptadec-8-ene); and (c) emission in all treatments, but enhanced in the dark (cyclic beta-ionone endoperoxide, dihydro beta-ionone and beta-ionone and total volatiles).
PT:  Journal-article
AN:  20000314264

Record 77 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Aroma studies of fruits and wine in Israel.
AU:  Bravdo-B; Shoseyov-O; Bravdo-BA
SO:  Proceedings of the Fifth International Symposium on Grapevine Physiology, Jerusalem, Israel, 25-30 May, 1997. Acta-Horticulturae. 2000, No. 526, 399-406; 14 ref.
LA:  English
AB:  Bound and free aroma compound analysis in must and wines produced in Israel showed ratios of bound to free varying between 1 and 4. In order to utilize this aroma potential efforts were made to find enzymes capable of hydrolysing the glycosidic bonds. Selection of microorganisms grown on medium consisting of monoterpene glycosides as a sole carbon source and adjusted to a pH of 3.4 resulted in a specific Aspergillus niger which produces a unique beta-glucosidase capable of efficiently hydrolysing glycosides in wine and must. Sensory evaluation tests coincided well with GC-MS analyses, indicating an efficient enhancement in wine quality. The recent introduction of SPME extraction device during the last decade, has greatly improved our capabilities to extend our studies on the effect of cultural practices on aroma components. In field studies we have found that P fertilizer application had positively affected leaf P content and bound aroma compounds as well as wine score by sensory evaluation in cv. Cabernet sauvignon. Irrigation with saline water significantly affected 16 various volatiles in Cabernet sauvignon in the southern arid zone of Israel (the Ramat Negev region). Moderate salinity of 2.7 dS/m in the irrigation water was found to enhance wine quality as determined by sensory evaluation. Growing Cabernet sauvignon on Ruggeri rootstock was found to enhance the aroma and the wine quality in comparison to similar vines on Salt creek rootstocks.
PT:  Conference-paper; Journal-article
IB:  90-6605-872-2
AN:  20000314708

Record 78 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Formation of volatile branched chain esters in bananas (Musa sapientum L.).
AU:  Wyllie-SG; Fellman-JK
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2000, 48: 8, 3493-3496; 17 ref.
LA:  English
AB:  Substrates controlling the formation of branched chain volatile esters in ripening bananas were investigated by the application of alcohol and amino acid precursors to whole fruit and tissue samples. The resulting changes in the profile of the volatile esters were determined using SPME and GC. These changes revealed the selectivity characteristics of the esterification enzyme AAT, the availability of acyl CoA's for ester formation, and the role of substrate supply on volatile production. The results obtained suggest that substrate supply is a major determinant of the quantitative and qualitative composition of the resulting aroma profile.
PT:  Journal-article
AN:  20000314979

Record 79 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Epicuticular wax of juvenile Eucalyptus leaves and headspace analysis of leaf volatiles.
AU:  Wirthensohn-MG; Sedgley-M; Jones-GP
SO:  Journal-of-Essential-Oil-Research. 2000, 12: 4, 401-411; 37 ref.
LA:  English
AB:  This study was performed to determine the variation in leaf epicuticular wax composition and yield between 17 species of Eucalyptus (growing at the Waite Agricultural Research Institute, South Australia) with horticultural potential, and to identify a possible solvent for epicuticular wax using headspace volatile analysis. Variation in the amount and composition of leaf epicuticular wax among the 17 species was characterized by GC, TLC and GC/MS. Across species, wax yield ranged from 0.7 to 4.5 mg/cm2. The major wax constituents in all species except E. delegatensis, were beta-diketones (24.7-83.0%), followed by wax esters (6.4-26.5%), n-alkanes (3.5-26.5%), fatty acids (3-15.9%), n-alcohols (0.6-11.1%) and aldehydes (0-9.2%). In E. delegatensis, the major wax constituents were wax esters (46.6%), beta-diketones (24.7%), n-alkanes (11.5%), fatty acids (7.5%), n-alcohols (5.2%) and aldehydes (4.3%). Volatile organic compounds emitted from developing Eucalyptus leaves of six species were studied using solid phase microextraction (SPME), and were analysed by GC and GC/MS. Leaf oils were extracted from four of the six species and the relative amounts of volatile compounds in the extract and headspace compared. The major volatile constituents were alpha-pinene (11.4-57.8%, headspace; 15.3-32.2%, oil extract) and 1,8-cineole (3.2-88.6%, headspace; 20.8-54.7%, oil extract). Other terpenoids present in the headspace in significant quantities were allo-aromadendrene, viridiflorene, alpha-thujene, alpha-phellandrene, gamma-terpinene and limonene. In the oil extract, allo-aromadendrene, alpha-phellandrene, viridiflorene and limonene were present in significant quantities. Components of leaf oils are potential solvents involved in the transport of waxes from the epidermis to the cuticle, although this is not confirmed by the present study.
PT:  Journal-article
AN:  20000315710

Record 80 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Shelf-life prediction of processed milk by solid-phase microextraction, mass spectrometry, and multivariate analysis.
AU:  Marsili-RT
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2000, 48: 8, 3470-3475; 12 ref.
LA:  English
AB:  A technique based on solid-phase microextraction, mass spectrometry, and multivariate analysis (SPME-MS-MVA) was used to predict the shelf life of pasteurized and homogenized reduced-fat milk and whole-fat chocolate milk sampled over a 7-month period. Using SPME-MS-MVA, which is essentially a mass spectrometry-based electronic-nose instrument, volatile bacterial metabolites were extracted from milk with SPME (Carboxen-PDMS) and injected into a gas chromatography capillary column at elevated temperature. Mass fragmentation profiles from the unresolved milk volatile components were normalized to the intensity of a chlorobenzene internal standard mass peak (m/z 112) and subjected to MVA. Prediction models based on partial least-squares regression of mass intensity lists were able to predict the shelf life of samples to approximately ±1 day, with correlation coefficients >0.98 for the 2 types of milk samples. Using principal component analysis techniques, the procedure was also useful for classifying samples that were rendered unpalatable by nonmicrobial sources (contamination by copper and sanitizer) as well as by bacteria.
PT:  Journal-article
AN:  20000405999

Record 81 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Clean recovery and HRGC-MS/HRGC-FTIR identification of volatiles from soybean (Glycine max).
AU:  Damiani-P; Cossignani-L; Castellini-M; Bin-F
SO:  Italian-Journal-of-Food-Science. 2000, 12: 2, 175-182; 19 ref.
LA:  English
LS:  Italian
AB:  Volatiles from soyabean leaves (Glycine max., var. Canton) were investigated to gain knowledge about these compounds for developing new methods to control phytophagous insects in soyabean fields. To extract the volatiles, two methods based on analysis of the dynamic headspace were used: thermal desorption cold trap injector (TCTI) and purge and trap injector (PTI). The separation of the compounds was carried out by gas chromatography with mass spectroscopy (HRGC-MS) and Fourier-transform infrared spectroscopy (HRGC-FTIR). The most abundant compounds were represented by: (Z)-3-hexenyl-acetate, 1-hexanol, (Z)-3-hexen-1-ol and 1-octen-3-ol. The addition of an internal standard to the samples allowed semiquantitative data to be accumulated. Solid phase microextraction (SPME) was used to characterize the profile of the volatiles from homogenized soyabean leaves. There were substantial differences in comparison to the profile obtained from intact leaves; this should be due to the chemical and enzymatic modifications occurring during homogenization.
PT:  Journal-article
AN:  20001114259

Record 82 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Alternative procedures for isolation and HRGC-MS/HRGC-FTIR characterization of volatiles from Nezara viridula.
AU:  Damiani-P; Cossignani-L; Castellini-M; Bin-F
SO:  Italian-Journal-of-Food-Science. 2000, 12: 2, 183-189; 12 ref.
LA:  English
LS:  Italian
AB:  Studies was carried out to isolate and determine volatile compounds from Nezara viridula, a phytophagous pest of some legumes, including soyabean, Glycine max. Knowledge of these volatiles may be important because they could be kairomones used to attract natural enemies in the control of pests of soyabean, a legume of particular importance in human nutrition. To collect the volatile compounds from N. viridula, Tenax GC [poly (2,6-diphenyl-p-phenylene oxide)] was used as adsorbent material. High resolution gas chromatography with a mass selective detector (HRGC-MS) and a Fourier transformed infrared spectroscopy detector (HRGC-FTIR) were used to separate and identify the volatiles. The compounds of the pheromonal blend, (Z)-alpha-bisabolene and (Z)-alpha-bisabolene epoxide, were isolated, but in some cases they were contaminated by compounds of the secretory glands, in particular tridecane. An alternative extraction system, solid phase microextraction (SPME), was also used.
PT:  Journal-article
AN:  20001114260

Record 83 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Rapid determination of pesticide residues in honey by SPME-HRGC-NPD and SPME-HRGC-ECD.
OT:  Determinazione rapida di residui di fitofarmaci nel miele mediante SPME-HRGC con rivelazione NPD ed ECD.
AU:  Galarini-R; Cossignani-L; Simonetti-MS; Ruffini-N; Marchetti-C; Luneia-R; Damiani-P
SO:  1° Assemblea Annuale dei Soci ed Evento Scientifico. Salsomaggiore, Italy, 13 novembre, 1998. Selezione-Veterinaria. 2000, Suppl., s417-s422; 5 ref.
LA:  Italian
LS:  English
AB:  A multiresidue method for the analysis of pesticide residues in honey by solid phase micro extraction (SPME) is reported. In recent years the procedures for the extraction of pesticide residues from different matrices have been developed in order to reduce the consumption of solvents. In particular, solid-phase extraction procedures (SPE) are more used than the liquid-liquid extraction ones (LLE) as they are much less expensive and result in less contamination. The SPME is a fast, solventless alternative to conventional sample extraction techniques in which a phase-coated fused silica fibre is immersed in a liquid sample or exposed to the headspace above a liquid or solid sample. Analytes adsorb to the phase and then are thermally desorbed in the injection port of a gas chromatograph and transferred to a capillary column. Few applications of SPME have been reported for the analysis of pesticide residues in foods. The analysis of pesticides in honey has importance because this matrix is subject to several sources of pollution. In this work the following residues were considered: bromopropylate, chlorfenvinphos, coumaphos, diazinon, ethion, malathion, pirimphos-methyl and terbufos. The extraction of pesticides was carried out by SPME using a 100 µm polydimethylsiloxane (PDMS) fibre. Known amounts of reference compounds were added to a honey sample free from pesticide residues in order to evaluate the response of the detectors, the linearity range and the detection limits. The following concentrations were considered: 10-20-40-80-160-320 µg/kg. The obtained results showed good linearity (r2=0.986-0.998) for all the eight pesticide residues in the considered range, 10-320 ppb. The detection limits, obtained considering the ratio signal/noise=3, from the responses of the 10 ppb sample, were in the range 0.5-4 ppb. As far as regressions and detection limits are concerned, the reported results for each compound are relative to the responses obtained with the detector which gives the best performances for that residue. Better results were obtained with NPD detection for diazinon, terbufos, pirimiphos-methyl, chlorfenvinphos, ethion, coumaphos and with ECD detection for malathion and bromopropylate. Nevertheless, apart from pirimiphos-methyl and bromopropylate, both the detectors could be used with obvious advantages deriving from comparison of the qualitative and quantitative results. In conclusion, the presented procedure has given satisfactory results for all the considered pesticide residues for both linearity range and detection limits. Moreover the SPME allows sample extraction and purification to be carried out in one step without the use of solvents so that both the time and contamination can be considerably reduced.
PT:  Conference-paper; Journal-article
AN:  20001114590

Record 84 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Occurrence of volatile secondary metabolites in selected Allium wild types.
OT:  Vorkommen fluchtiger Sekundarmetabolite in ausgewahlten Allium-Wildtypen.
AU:  Schulz-H; Kruger-H; Herchert-N; Keller-ERJ
SO:  Secondary plant compounds. Proceedings of a symposium held at the Biological-Pharmaceutical Faculty, Friedrich-Schiller University, Jena, Germany, 30 September to 2 October, 1999. Journal-of-Applied-Botany. 2000, 74: 3-4, 119-121; 7 ref.
LA:  German
LS:  English
AB:  Six different Allium wild genotypes were analyzed for their individual composition of volatile sulphur components. The species studied were as follows: A. obliquum, A. senescens, A. saxatile, A. globosum, A. chevsuricum and A. altyncolicum. In order to achieve a fast and reliable description of the aroma profiles a new developed solid phase micro extraction (SPME)-GC method was applied. In comparison to the usually performed simultaneous distillation-extraction (SDE) procedure, direct SPME analysis permits easy monitoring of the most valuable sulphur-containing volatiles. Based on the individual GC profiles the influence of the different genetic background on the aroma composition was clearly demonstrated. Furthermore, an objective of this study was to present the use of a newly developed method for chemotaxonomic interpretations of species relationships.
PT:  Conference-paper; Journal-article
AN:  20001617696

Record 85 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Determination of compound-specific carbon isotope ratios of chlorinated methanes, ethanes, and ethenes in aqueous samples.
AU:  Hunkeler-D; Aravena-R
SO:  Environmental-Science-and-Technology. 2000, 34: 13, 2839-2844; 36 ref.
LA:  English
AB:  Compound-specific carbon isotope ratio analysis is a promising tool to assess the origin and fate of organic contaminants in groundwater. The aim of this study was to develop and evaluate a reliable, fast method to determine carbon isotope ratios of chlorinated methanes, ethanes, and ethenes in aqueous samples. Direct solid-phase microextraction (dSPME) and headspace solid-phase microextraction (hSPME) were selected as extraction method and compared to headspace equilibration. For dSPME and hSPME, deviations between carbon isotope ratios in the aqueous phase and on the SPME fibre were _0.40%. For headspace equilibration, molecules in the gas phase were enriched in 13C compared to molecules in the aqueous phase by up to 1.46%, in particular for chlorinated methanes. The absence of significant carbon isotope fractionation during dSPME and hSPME could be explained by the fact that both the aqueous phase and the SPME fibre coating discriminate against molecules with 13C to a similar degree, and thus no net carbon isotope fractionation occurs. If aqueous phase/gas-phase carbon isotope fractionation during headspace equilibration is taken into account, all methods, dSPME, hSPME, and headspace equilibration, provide accurate delta13C values with a similar precision. Direct SPME was the most sensitive method with detection limits as low as 130 ppb.
PT:  Journal-article
AN:  20001915037

Record 86 of 187 in CAB Abstracts 2000/08-2001/07

TI:  In-tube solid-phase microextraction coupled to capillary LC for carbamate analysis in water samples.
AU:  Gou-YanNi; Pawliszyn-J; Gou-YN
SO:  Analytical-Chemistry-Washington. 2000, 72: 13, 2774-2779; 11 ref.
LA:  English
AB:  Recently, the on-line sample preparation technique, in-tube solid-phase microextraction (SPME), was successfully implemented with a Hewlett-Packard 1100 HPLC system for analysis of carbamates in water samples. The paper describes the coupling of in-tube SPME to capillary liquid chromatography (LC) and explores its utility as a sample preparation method in that format, relative to conventional LC. The Hewlett-Packard HPLC system was upgraded to a capillary LC system using commercially available accessories from LC Packings. The combination of in-tube SPME with a capillary LC system was expected to build on the merits of both in-tube SPME and the capillary LC to generate a sensitive method with an easy, effective, and efficient sample preparation. Due to the relatively large effective injection volume of the in-tube SPME technique (30-45 µl), on-column focusing was used in order to achieve good chromatographic efficiency. For all carbamates studied, the RSD of retention time was between 0.5 and 0.8% under 4 µl/min microgradient conditions. The RSD of peak area counts was between 1.5 and 4.6%. The detection limits for all carbamates studied were less than 0.3 µg/l and, for carbaryl, just 0.02 µg/l (20 ppt). Compared with the conventional in-tube SPME/LC method, the LODs were lowered for carbaryl, propham, methiocarb, promecarb, chlorpropham, and barban, by factors of 24, 45, 42, 81, 62, and 56, respectively. The optimized method was successfully applied to the analysis of carbamates in surface water samples.
PT:  Journal-article
AN:  20001915340

Record 87 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Solid phase microextraction/gas chromatography of Salmonella-infected beef.
AU:  Ogihara-H; Horimoto-Y; Wang-ZhiHai; Skura-BJ; Nakai-S; Wang-ZH
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2000, 48: 6, 2253-2259; 7 ref.
LA:  English
AB:  Eight strains of Salmonella were incubated in TSB culture medium at 37°C for 24 h. Volatile compounds derived from the bacteria were collected using solid-phase microextraction fibres and then applied to gas chromatography (GC). Similarity analysis of the GC patterns thus obtained could separate these strains on principal component similarity (PCS) scattergrams. Five major food-related pathogenic bacteria and 10 other bacteria (including 1 Salmonella strain) were also classified by growing in the same medium. It is then proposed to utilize this approach to improve the GC/PCS method of Nakai et al. [Journal of Agricultural and Food Chemistry (1999) 47, 576-583] that has been developed for screening safe foods by detecting bacteria contaminated foods. Inoculating food samples pre-enriched through preliminary incubation into a culture medium and then subjecting to the GC/PCS method after secondary incubation enhances the detectability of pathogenic bacteria.
PT:  Journal-article
AN:  20002221493

Record 88 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Use of stable tracer studies to evaluate pesticide photolysis at elevated temperatures.
AU:  Hebert-VR; Hoonhout-C; Miller-GC
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2000, 48: 5, 1916-1921; 25 ref.
LA:  English
AB:  New methods were developed to determine photolysis rates of medium-weight pesticides in the gas phase using elevated air temperatures and solid-phase microextraction (SPME). A 57-L glass chamber was constructed that utilized collimated xenon arc irradiation that could heat chamber air to increase the amount of pesticide in the gas phase. Gas-phase photolysis rates were determined at various air temperatures by comparing the rate of loss of each of the tested pesticides to a photochemically stable tracer, hexachlorobenzene. Interval sampling of gas-phase constituents was performed using SPME immediately followed by GC-ECD or GC-MSD analysis. The two pesticides under examination were the dinitroaniline herbicide trifluralin and the organophosphorus insecticide chlorpyrifos. The gas-phase photolysis for trifluralin was found to be rapid with half-lives of 22-24 minutes corrected for sunlight. These results were comparable to photochemical lifetime estimates from other investigators under sunlight conditions. Elevating temperatures from 60 to 80°C did not affect photolysis rates, and these rates could be extrapolated to environmental temperatures. From 60 to 80°C, gas-phase chlorpyrifos photolysis lifetimes were observed to range from 1.4 to 2.2 h corrected for sunlight and will thus be important together with hydroxyl radical reactions for removing this substance from the atmosphere. At these elevated temperatures, pesticides and tracer compounds were found to be substantially in the gas phase, and possible effects on reaction rates from wall interactions were minimized.
PT:  Journal-article
AN:  20002303529

Record 89 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Chemical composition of the essential oil and headspace solid-phase microextraction of the guava fruit (Psidium guajava L.).
AU:  Paniandy-JC; Chane-Ming-J; Pieribattesti-JC
SO:  Journal-of-Essential-Oil-Research. 2000, 12: 2, 153-158; 25 ref.
LA:  English
AB:  The essential oil and headspace of fresh white-flesh guava fruits from trees grown in Reunion island were obtained by steam hydrodistillation and headspace solid-phase microextraction (SPME), respectively. The chemical composition of the extract was investigated by GC and GC-MS. A total of 73 compounds were identified, 61 by hydrodistillation and 24 by headspace SPME. In the headspace, the major constituents were: hexanal (65.9%), gamma-butyrolactone (7.6%), (E)-2-hexenal (7.4%), (E,E)-2,4-hexadienal (2.2%), (Z)-3-hexenal (2%), (Z)-2-hexenal (1%), (Z)-3-hexenyl acetate (1.3%) and phenol (1.6%), while beta-caryophyllene (24.1%), nerolidol (17.3%), 3-phenylpropyl acetate (5.3%) and caryophyllene oxide (5.1%) were the major volatile constituents present in the hydrodistilled essential oil. Many compounds were identified for the first time in fruits such as gamma-butyrolactone (7.6%) in the headspace SPME and nerolidol (17.6%) in the essential oil. In addition some compounds such as (Z)-3-hexenal, (E,E)-2,4-hexadienal, gamma-butyrolactone, borneol, phenol, cuminyl alcohol could be identified only by the headspace method.
PT:  Journal-article
AN:  20000310829

Record 90 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Analysis of the aroma compounds of the pulp of Borassus aethiopum L. (Palmaceae) from Cameroon using GC-MS, SPME-GC-MS and olfactometry.
AU:  Jirovetz-L; Buchbauer-G; Ngassoum-MB
SO:  Ernahrung. 2000, 24: 4, 159-161; 6 ref.
LA:  English
LS:  German
AB:  The aroma compounds of the pulp of B. aethiopum fruits from Cameroon were analysed by GC-FID, SPME-GC-FID, GC-MS, SPME-GC-MS and olfactoric evaluations. Qualitative and quantitative differences were observed in the compositions of essential oil, headspace extract and SPME extract, with the essential oil dominated by monoterpenes and the SPME extract dominated by lower esters. More than 40 volatiles were identified. The characteristic odour impression of the essential oil and headspace-sample could be attributed to the main compounds of each sample, including limonene, beta-pinene and gamma-terpinene (monoterpenes), and butanoic acid ethyl ester, acetic acid ethyl ester, and hexanoic acid ethyl ester (lower esters).
PT:  Journal-article
AN:  20000311063

Record 91 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Monoterpene biosynthesis in Mentha X piperita L.: bioconversion of piperitone and piperitenone.
AU:  Fuchs-S; Gross-A; Beck-T; Mosandl-A
SO:  Flavour-and-Fragrance-Journal. 2000, 15: 2, 84-90; 15 ref.
LA:  English
AB:  Mentha piperita shoot tip and first leaf pair were fed with aqueous solutions of deuterium-labelled racemic piperitone and achiral piperitenone. The essential oil was extracted by solid phase micro-extraction (SPME) and subsequently analysed using enantioselective multidimensional gas chromatography/mass spectrometry (enantio-MDGC-MS). Both labelled precursors led to the corresponding 1R-configured p-menthan-3-ones (-)-menthone and (+)-isomenthone, favouring the labelled (+)-isomenthone.
PT:  Journal-article
AN:  20000312410

Record 92 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Volatile changes during dehydration of d'Agen prunes.
AU:  Sabarez-HT; Price-WE; Korth-J
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2000, 48: 5, 1838-1842; 30 ref.
LA:  English
AB:  Solid phase microextraction (SPME) was used in conjunction with GC-MS to monitor the changes in some major volatile flavours during drying of plums. The aroma profile was significantly modified during the process and substantial loss of the original volatile flavours was observed. The generation of some compounds was shown to be due to the thermal decomposition of carbohydrates. This paper discusses the importance of aroma profiling in detecting the progress of the chemical (degradation) reactions and identifying marker volatiles in quality control of the product.
PT:  Journal-article
AN:  20000312804

Record 93 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Evaluation of solid-phase microextraction for the isotopic analysis of volatile compounds produced during fermentation by lactic acid bacteria.
AU:  Goupry-S; Rochut-N; Robins-RJ; Gentil-E
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2000, 48: 6, 2222-2227; 14 ref.
LA:  English
AB:  The use of solid-phase microextraction (SPME) coupled with isotope ratio mass spectrometry (IRMS) for the analysis of flavour compounds produced by lactic acid bacteria was evaluated using liquid and headspace sampling modes. Initially, it was necessary to optimize the conditions for the SPME extraction of flavours - diacetyl and acetoin - in standard aqueous solutions. The effects of salt, headspace vs. liquid sampling, and coating phase were tested. Second, the suitability of the coupling of SPME and gas chromatography - combustion interface - IRMS (GC-C-IRMS) for the determination of delta13C values was assessed. Neither the analyte concentration nor the period of fibre exposure has an effect on the delta13C values. Finally, having verified that there are no matrix effects from the fermentation medium, it is reported for the first time that flavour compounds can be extracted directly from culture supernatant by SPME and their delta13C values can be obtained by GC-C-IRMS.
PT:  Journal-article
AN:  20000405063

Record 94 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Comparison of headspace techniques for sampling volatile natural products in a dynamic system.
AU:  Faldt-J; Eriksson-M; Valterova-I; Borg-Karlson-AK
SO:  Zeitschrift-fur-Naturforschung.-Section-C,-Biosciences. 2000, 55: 3-4, 180-188; 17 ref.
LA:  English
AB:  Commonly used dynamic sorption techniques for collecting biologically active volatile compounds have been compared. Solid phase microextraction (SPME) using two types of fibres (polydimethylsiloxane, PDMS, 100 µm, and carbowax/divinylbenzene, CW/DVB, 65 µm) was compared to purge and trap methods (Porapak Q, Tenax TA and charcoal) and a technique based on absorption in methanol in a cooling bath. Sampling was done in a stream of purified air (20 ml/min) in a closed and temperature-regulated (27°C) glass tube, passing over a capillary tube containing a hexane solution of tridecane, heptadecane, 1-octen-3-ol, 1-hexadecanol, ethyl tetradecanoate, alpha-pinene, linalool, terpinene-4-ol, cis-verbenol, verbenone, beta-caryophyllene, E,E-farnesol, and geranylgeraniol. With all of the methods, the sampling was performed for a period of 30 min before extraction and analysis was done on a GC-FID system. In general, SPME gave a higher response for all compounds except for alpha-pinene, which was only extracted by the CW/DVB fibre. Purge and trap methods and methanol absorption gave the same response for all substances extracted. None of the methods extracted hexadecanol and geranylgeraniol under the conditions used. However, the SPME equipped with the PDMS coating extracted heptadecane, E,E-farnesol and ethyl tetradecanoate. These results show that SPME, when selecting the fibres to fit the polarity and volatility of the compounds, is an outstanding extraction method compared to purge and trap and methanol absorption, especially for a qualitative analysis. The best conditions for storing fibres exposed to compounds of high volatility were at low temperatures (6°C) in sealed vials, while the worst way was to leave the exposed fibre unprotected at room temperature (22°C). The dynamic sampling system was effectively tested on a fruiting body of a polypore fungus (Ganoderma applanatum) emitting 1-octen-3-ol, and again SPME showed to be the most sensitive technique.
PT:  Journal-article
AN:  20001109896

Record 95 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Are variations in cuticular hydrocarbons of queens and workers a reliable signal of fertility in the ant Harpegnathos saltator?
AU:  Liebig-J; Peeters-C; Oldham-NJ; Markstadter-C; Holldobler-B
SO:  Proceedings-of-the-National-Academy-of-Sciences-of-the-United-States-of-America. 2000, 97: 8, 4124-4131; 69 ref.
LA:  English
AB:  One of the key features of insect societies is the division of labour in reproduction between one or a few fertile individuals and many sterile nestmates that function as helpers. The behavioural and physiological mechanisms regulating reproduction in ant societies are still not very well understood, especially in species in which all colony members are reproductively totipotent. In the ponerine ant Harpegnathos saltator, queen-worker dimorphism is very limited, and a few mated workers reproduce ("gamergates") once the founding queen becomes senescent. Worker oviposition is regulated by highly directed aggressive interactions among nestmates, who can recognize different levels of ovarian activity. We show that variations in cuticular hydrocarbons (CHC) correlate with oogenesis, both for queens and workers. 13,23-Dimethylheptatriacontane is present in egg-layers, but not in infertile workers and queens. Proportions of other CHCs vary as well, resulting in clear separation of the ants in a multivariate analysis. Egg-layers are characterized by an elongation of the chain length of CHCs. We used solid-phase microextraction to measure CHCs in live ants that were experimentally induced to start producing eggs. Over a period of 118 days, CHC profiles of infertile workers changed completely to that of reproductives. The effect of age can be excluded in this modification. This striking correlation of ovarian activity with CHC variation and its correspondence with the observed recognition behaviour exhibited by the workers toward egg-laying nestmates suggests that CHCs serve as a fertility signal in the ant H. saltator, a reliable basis for regulating reproduction.
PT:  Journal-article
AN:  20001110727

Record 96 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Application of Solid Phase Micro-Extraction (SPME) to the analysis of pesticide residues in vegetables.
AU:  Volante-M; Pontello-M; Valoti-L; Cattaneo-M; Bianchi-M; Colzani-L
SO:  Pest-Management-Science. 2000, 56: 7, 618-636; 23 ref.
LA:  English
AB:  Solid Phase Micro-Extraction (SPME) is a new analytical technique, based on capturing the analytes by adsorption onto an organic phase coating a glass fibre, and subsequent direct desorption into the injector of a gas chromatograph. This technique has been successfully applied in the analysis of organic contaminants in water, giving linear responses and, in some cases, high sensitivities. The present paper reports data about the application of SPME to the analysis of pesticide residues in a vegetable matrix, testing over nearly one hundred active compounds, with two types of adsorbent phase (polydimethylsiloxane and Carbowax/divinylbenzene). A vegetable matrix spiked with pesticides was analysed by SPME and by a traditional multi-residue method; recoveries were determined and compared for the two cases. The behaviour of the analytical response by SPME was studied in the range 0.01-1 mg kg-1 by adding increasing amounts of given pesticide mixtures to the vegetable matrix. The procedure was further tested by analysing real samples, and gave some difficulties in recovering the whole amount of some of the residues present (in comparison with the traditional method). The SPME method was then improved by pre-extracting with acetone and sonicating before the extraction/adsorption step. The results obtained were satisfactory (some certified matrices were also tested) with good accordance between the two methods. Nevertheless some active compounds showed very low responses or remained undetectable by SPME in our experimental conditions.
PT:  Journal-article
AN:  20001111209

Record 97 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Reactivity of certain organophosphorus insecticides toward hydroxyl radicals at elevated air temperatures.
AU:  Hebert-VR; Hoonhout-C; Miller-GC
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2000, 48: 5, 1922-1928; 23 ref.
LA:  English
AB:  Methods were developed to determine OH reaction rates for medium-weight organophosphorus pesticides in the gas phase. A 57-L chamber was constructed that utilized xenon arc irradiation (>290 nm) to photolyze the OH precursor, methyl nitrite. Experiments were performed at elevated temperatures ranging from 60 to 80°C to minimize wall sorption. Solid-phase microextraction (SPME) sampling of the gas phase was employed to assess the simultaneous rate of loss of the pesticides in relation to the rate of loss of two reference substances with known OH rate constants. An internal gas-phase standard (hexachlorobenzene), relatively stable to hydroxyl radicals, was used to assess other processes, which included dilution and wall sorption. The relative reaction rates of the organophosphorus insecticides, diazinon and chlorpyrifos, when compared to reference compounds, were unaffected by various air temperatures between 60 and 80°C. Although both insecticides were expected to react at similar rates on the basis of structural activity model predictions, diazinon reacted 3 times more rapidly than chlorpyrifos and gave estimated environmental OH half-lives of 0.5 and 1.4 h, respectively. The degree of sorption onto the chamber walls was minimal and similar for each of the compounds examined. Experimental gas-phase determinations at elevated temperatures may provide important information that can be used when in the assessment of the potential of airborne pesticide risks to nontarget and ecologically sensitive areas.
PT:  Journal-article
AN:  20001111369

Record 98 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Frozen storage effects on anthocyanins and volatile compounds of raspberry fruit.
AU:  Ancos-B-de; Ibanez-E; Reglero-G; Cano-MP; de-Ancos-B
SO:  Journal-of-Agricultural-and-Food-Chemistry. 2000, 48: 3, 873-879; 26 ref.
LA:  English
AB:  The quantitative and qualitative evolution of the anthocyanins and volatile compounds of four raspberry cultivars (Heritage, Autumn Bliss, Zeva and Rubi) growing in Spain were analyzed raw, just frozen, and during long-term frozen storage at -20°C for a 1 year period. HS-SPME coupled with GC-MS and HPLC techniques were employed to study the evolution of the volatile compounds and the individual anthocyanins, respectively. The volatile aroma composition changes produced by the freezing process and long-term frozen storage were minimal. The only significant increase in extraction capacity was obtained for alpha-ionone (27%) and for caryophyllene (67%) in Heritage at 12 months of storage. The stability of anthocyanins to freezing and frozen storage depends on the seasonal period of harvest. Heritage and Autumn Bliss (early cultivars) were less affected by processing and long-term frozen storage (1 year), and the total pigment extracted showed the tendency to increase 17 and 5%, respectively. Rubi and Zeva (late cultivars) suffered a decreased trend on the total anthocyanin content of 4% for Rubi and 17.5% for Zeva. Cyanidin 3-glucoside most easily suffered the degradative reactions that take place during processing and the storage period.
PT:  Journal-article
AN:  20001612216

Record 99 of 187 in CAB Abstracts 2000/08-2001/07

TI:  Use of solid-phase microextraction for the quantitative determination of herbicides in soil and water samples.
AU:  Hernandez-F; Beltran-J; Lopez-FJ; Gaspar-JV
SO:  Analytical-Chemistry-Washington. 2000, 72: 10, 2313-2322; 38 ref.
LA:  English
AB:  An in-depth study of SPME optimization and application was made, considering not only aqueous (surface water and groundwater samples) but also the more complex soil samples. Seven herbicides widely used in the area of study in Spain were selected including five triazine herbicides (atrazine, simazine, terbumeton, terbuthylazine, terbutryn), molinate, and bromacil. Linearity range was between 0.1 and 10 ng/ml and the repeatability below 10% when applying the optimized SPME procedure to water samples. Reproducibility was found to be lower than 20% at the 1 ng/ml level, and the limits of determination in environmental water samples using GC/MS (SIM mode) were well below 0.1 ng/ml (values ranging from 10 to 60 ng/litre). Extraction of selected herbicides from soil was carried out by microwave-assisted solvent extraction using methanol in screw-capped vials, leading to recoveries over 80% in spiked soil samples at the 5-200 ng/g level. SPME application over methanolic soil extracts required a 10-fold dilution with distilled water. The recommended procedure was found to be fully applicable for quantitative determination of selected herbicides in soils containing low organic matter content with coefficients of variation below or around 10% and limits of determination ranging from 1 to 10 ng/g. Both procedures were applied to real-world surface water and soil samples where several pesticides were detected including atrazine, simazine, terbuthylazine, and molinate.
PT:  Journal-article
AN:  20001913698

Record 100 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Solid phase microextraction of volatile constituents from individual fresh Eucalyptus leaves of three species.
AU:  Betts-TJ
SO:  Planta-Medica. 2000, 66: 2, 193-195; 3 ref.
LA:  English
AB:  Methyl polysiloxane solid-phase microextraction fibres were used for ten minutes to adsorb volatile constituents from headspace above all or part of a single cut up fresh eucalyptus leaf kept warm at 37oC. The fibres were desorbed at 200oC for programmed gas chromatography (40-187oC) on a methyl polysiloxane capillary. Substances were identified by mass spectra and/or authentic sample retention. Results did not correspond to published values for steam distilled oils, being richer in sesquiterpenes, of which three are common to three different species; and also in esters in two species. Five Eucalyptus citriodora leaves from the same tree over different months gave very similar analyses to a fibre in 10 min of 72.9-80.5% citronellal, 3.5-5.4% citronellol, 1.0-3.8% citronellyl acetate, 9.2-11.8% caryophyllene and 1.4-1.7% bicyclogermacrene. Six E. nicholii leaves yielded 67.2-73.7% cineole [eucalyptol] and 4.6-9.7% limonene along with 10.5-16.5% sesquiterpenes, mostly hydrocarbons, particularly bicyclogermacrene. E. globulus leaves gave only 54.0-61.3% cineole, with 19.5-24.3% alpha-pinene, 6.7%-9.1% limonene and 2.1-5.4% alpha-terpinyl acetate; along with 3.6-7.7% sesquiterpenes, particularly aromadendrene, but no bicyclogermacrene.
PT:  Journal-article
AN:  20000310638

Record 101 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Absorption of hydrophobic compounds into the poly(dimethylsiloxane) coating of solid-phase microextraction fibers: high partition coefficients and fluorescence microscopy images.
AU:  Mayer-P; Vaes-WHJ; Hermens-JLM
SO:  Analytical-Chemistry-Washington. 2000, 72: 3, 459-464; 23 ref.
LA:  English
AB:  The use of solid-phase microextraction with poly(dimethylsiloxane) (PDMS)-coated glass fibres for the extraction and analysis of hydrophobic organic analytes is increasing. A new method, which minimizes the impact of experimental artifacts was applied to determine PDMS water partition coefficients of 17 hydrophobic analytes including chlorinated benzenes, PCBs, PAHs, and p,p'-DDE. These partition coefficients are several orders of magnitude higher than some reported values. Two observations strongly suggested that the retention of hydrophobic organic substances is governed by partitioning into the PDMS coating. The partition coefficients were proportional with octanol/water partition coefficients. The fluorescence of fluoranthene was observed to be homogeneously distributed within the polymer coating when studied by means of fluorescence microscopy. The implications of these findings for the application of solid-phase microextraction with respect to potential detection limits, with respect to biomimetic extraction, and with respect to measurements in multicompartment systems are discussed.
PT:  Journal-article
AN:  20001108175

Record 102 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Sex pheromones of Phyllonorycter acerifoliella and Ph. heegerella and communication peculiarities in three species of leafmining moths.
AU:  Mozuraitis-R; Buda-V; Jonusaite-V; Borg-Karlson-AK; Noreika-R
SO:  Entomologia-Experimentalis-et-Applicata. 2000, 94: 1, 15-23; 12 ref.
LA:  English
AB:  Females of the leaf miners Phyllonorycter sylvella and P. heegerella (Lepidoptera: Gracillariidae: Lithocolletinae) release their sex pheromone at the beginning of the photophase. The periodicity of the 'calling' behaviour of P. sylvella females was established. Three compounds from calling virgin P. heegerella females were collected by the Solid Phase Micro Extraction (SPME) technique and identified as (Z)-8-tetradecenyl acetate (Z8-14:OAc), tetradecyl acetate (14:OAc) and (Z)-8-tetradecenol (Z8-14:OH) in the ratio (88±3):(2±0.6):(10±5) by capillary gas chromatography and mass spectrometry. Field trapping experiments demonstrated that the first two compounds are important for the attraction of conspecific males. Z8-14:OAc was found to be attractive when tested separately, while 14:OAc acted as synergist. The attractivity of the three component blend was reduced by 10% admixture of either (E)-10-dodecenyl acetate (E10-12:OAc) or (Z)-10-tetradecenyl acetate (Z10-14:OAc). Field tests of Z10-, Z8- and E10-14:OAc, identified from P. sylvella females, demonstrated that the first two compounds were essential for the attraction of conspecific males; so both are sex pheromone components. The attractivity of the three component blend of Z10-Z8- and E10-14:OAc was reduced by 10% admixture of (E)-10-dodecenol (E10-12:OH). The following four semiochemical compounds, Z8-14:OAc, Z8-14:OH, E10-14:OAc and 14:OAc, identified from phyllonoryctid females, as well as two sex attraction antagonists for P. sylvella and P. heegerella males, E10-12:OAc and Z10-14:OAc, are new for the family Gracillariidae. The results of field trapping experiments revealed mechanisms ensuring the specificity of the chemocommunication systems in P. sylvella, P. heegerella and P. ulmifoliella (Hb.) moths.
PT:  Journal-article
AN:  20001108360

Record 103 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Identification of pheromone synergists in American Palm weevil, Rhynchophorus palmarum, and attraction of related Dynamis borassi.
AU:  Rochat-D; Meillour-PN-le; Esteban-Duran-JR; Malosse-C; Perthuis-B; Morin-JP; Descoins-C; le-Meillour-PN
SO:  Journal-of-Chemical-Ecology. 2000, 26: 1, 155-187; 57 ref.
LA:  English
AB:  Thirteen host plant kairomone blends, including 28 compounds, were tested and showed moderate to high synergy with rhynchophorol. The blends + rhynchophorol also attracted the related Dynamis borassi. Ethanol-ethyl acetate blends in various ratios showed moderate synergy. Two blends, including 'characteristic coconut' odour molecules, were as efficient as sugarcane in synergizing rhynchophorol and field luring American Palm weevils (APWs). Preliminary olfactometer tests of natural host plant volatiles demonstrated the role of fermentation in primary APW attraction. The synergists were chosen from a comparative study of the odours emitted by four plant materials attractive to the APW: sugarcane, coconut, Jacaratia digitata tree and Elaeis guineensis (oil palm). The volatiles were isolated during 6 days of sequential trappings onto Supelpak-2 adsorbent. The highly volatile fraction of sugarcane volatiles was sampled by solid-phase microextraction (SPME). Odours were analysed and identified by gas chromatography and mass spectrometry. Electroantennogram responses to the plant odours were recorded to help in screening for bioactivity. The odour compositions between plants prior to and during fermentation were compared using a principal component analysis (PCA) to determine common odour features of the plants and to design simplified blends for field activity screening. About 100 components were identified in the >4-carbon fraction of the odours, among which 65% were fermentation volatiles. Fermentation generated a strong increase in the amount and variety of the volatiles emitted. The palm materials emitted two- to three-fold greater odour amounts than the other plants. The odours from each plant were distinct according to PCA, with few common abundant components: isopentanol, 2-methylbutanol, their acetates, acetoin, isobutyl acetate, 2,3-butanediol, and 2-phenylethanol. Ethanol and ethyl acetate accounted for 80-90% in the highly volatile fraction of sugarcane odours. Coconut odour was mainly characterized by phenol, guaracol, 1,2-dimethoxybenzene, ethyl esters of tiglic and 3,3-dimethylacrylic acids, 2-hexanone, 2-nonanone; and, to a lesser extent, by 2-heptanone, menthone, beta-phellandrene, ethyl octanoate and decanoate, which were also present in other plants.
PT:  Journal-article
AN:  20001108881

Record 104 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Bioaccumulation tests applied in whole effluent assessment: a review.
AU:  Maagd-PGJ-de; de-Maagd-PGJ; Oris-J (ed.); Klaine-S
SO:  Annual review. Whole effluent toxicity testing. Environmental-Toxicology-and-Chemistry. 2000, 19: 1, 25-35; 57 ref.
LA:  English
AB:  This paper discusses the potential additional value of including bioaccumulation parameters in whole effluent assessment and methods that can be used for routine assessment. It is concluded that screening on the presence of potentially bioaccumulating compounds leads to a more comprehensive hazard assessment and should therefore be included in whole effluent assessment. A chemical method to assess potentially bioaccumulating substances (PBSs) is preferred above methods using organisms or classical group parameters such as extractable organic halogens (EOX). In situ studies with organisms are not feasible for routine assessment for a number of reasons, including cost efficiency and matrix problems. Classical group parameters such as EOX do not relate to bioaccumulation or toxicity. Chemical methods for assessing bioaccumulation are usually presented as integrated methods composed of different procedure steps such as pretreatment, extraction, separation, and detection. However, an optimal method may be constructed by combining procedure steps from different reported methods. Solid phase microextraction combined with high performance liquid chromatography or gas chromatography combined with mass spectrometry is regarded as the preferable method for the assessment of PBSs. Before implementation in whole effluent assessment the method must be carefully validated. Hazard assessment based on bioaccumulation seems feasible. For risk assessment, however, additional information is a prerequisite. Quantitative causal relationships between test assay results and relevant effects on the population and ecosystem level are absent, hampering the desired upgrading from hazard to risk assessment.
PT:  Journal-article
AN:  20001908178

Record 105 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Source identification of underground fuel spills by solid-phase microextraction/high-resolution gas chromatography/genetic algorithms.
AU:  Lavine-BK; Ritter-J; Moores-AJ; Wilson-M; Faruque-A; Mayfield-HT
SO:  Analytical-Chemistry-Washington. 2000, 72: 2, 423-431.
LA:  English
AB:  Solid-phase microextraction (SPME), capillary column gas chromatography, and pattern recognition methods were used to develop a potential method for typing jet fuels so a spill sample in the environment can be traced to its source. The test data consisted of gas chromatograms from 180 neat jet fuel samples representing common aviation turbine fuels found in the USA (JP-4, Jet-A, JP-7, JPTS, JP-5, JP-8). SPME sampling of the fuel's headspace afforded well-resolved reproducible profiles, which were standardized using special peak-matching software. The peak-matching procedure produced 84 standardized retention time windows, though not all peaks were present in all gas chromatograms. A genetic algorithm (GA) was employed to identify features (in the standardized chromatograms of the neat jet fuels) suitable for pattern recognition analysis. The GA selected peaks, whose two largest principal components showed clustering of the chromatograms on the basis of fuel type. The principal component analysis routine in the fitness function of the GA acted as an information filter, significantly reducing the size of the search space, since it restricted the search to feature subsets whose variance was primarily about differences between the various fuel types in the training set. In addition, the GA focused on those classes and/or samples that were difficult to classify as it trained using a form of boosting. Samples that consistently classify correctly were not as heavily weighted as samples that were difficult to classify. Over time, the GA learned its optimal parameters in a manner similar to a perceptron. The pattern recognition GA integrated aspects of strong and weak learning to yield a 'smart' one-pass procedure for feature selection.
PT:  Journal-article
AN:  20001908208

Record 106 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Determination of chlorophenols in soils using accelerated solvent extraction combined with solid-phase microextraction.
AU:  Wennrich-L; Popp-P; Moder-M
SO:  Analytical-Chemistry-Washington. 2000, 72: 3, 546-551; 18 ref.
LA:  English
AB:  A method for the determination of chlorophenols in soil samples using accelerated solvent extraction (ASE) with water as the solvent combined with solid-phase microextraction (SPME) and GC/MS has been developed. Important ASE parameters, such as extraction temperature and time, were optimized using a spiked wetland soil. The effect of small amounts of organic modifiers on the extraction yields was studied. An extraction temperature of 125oC and 10 min extractions performed three times proved optimal. Two ASE-SPME procedures without and with an organic modifier (5% acetonitrile) were evaluated with respect to precision and detection limits (LOD). The reproducibility of replicate water extractions/SPME determinations (n=6) was in the range 7-20% relative standard deviation for the nine chlorophenols investigated. LOD values in the low-ppb range were achieved for all chlorophenols. The ASE-SPME procedure presented here was applied to the determination of chlorophenols in soil samples taken from contaminated areas near Bitterfeld, Germany.
PT:  Journal-article
AN:  20001909209

Record 107 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Development of a hollow waveguide sampler for detection of chlorinated aromatic compounds in soils.
AU:  Yang-Jyisy; Her-JyiWeoi; Yang-J; Her-JW
SO:  Analytical-Chemistry-Washington. 2000, 72: 4, 878-884; 40 ref.
LA:  English
AB:  A Fourier transform infrared (FT-IR) spectroscopic method for detection of chlorinated aromatic compounds in soils is presented. The sensing device of this method was based on an infrared hollow wave guide, the inner surface of which was coated with a hydrophobic film. Vapourized chlorinated aromatic compounds from soils were trapped onto the hydrophobic film of the hollow wave guide sampler following detection by FT-IR spectrometry. The extraction process in this method was similar to the headspace solid-phase microextraction (HSSPME) in principle. Means of increasing the speed of transfer of the vapourized organic species to the sampler were also studied. Results indicated that, with a negative pressure on the end of the sampler, the speed of transfer increased significantly. Vapour pressures of the analytes were used as an indication to test the limitation of this method in the analysis of organic compounds in soils. Results showed that analytes with vapour pressures lower than 12 Torr could be detected quantitatively. The typical R-square of the regression on the concentration and IR signals was around 0.99 and the typical detection limits were in the range of hundreds of parts per billion.
PT:  Journal-article
AN:  20001909480

Record 108 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Bioavailability in soil or sediment: exposure of different organisms and approaches to study it.
AU:  Sijm-D; Kraaij-R; Belfroid-A; Jones-KC (ed.); Gevao-B (ed.); Mordaunt-C (ed.); Northcott-G (ed.); Semple-KT
SO:  Special issue: non-extractable residues in soil and sediments: characterisation and environmental significance. Environmental-Pollution. 2000, 108: 1, 113-119; 40 ref.
LA:  English
AB:  Soil and benthic organisms may be exposed to contaminants via different routes: (pore) water, soil or sediment, and food. Depuration of the contaminant from the organisms may take place via the same routes and, additionally, via biotransformation, reproduction, etc. Whereas uptake from and depuration to water can be predicted well, predictions for soil or sediment are less accurate. One of the reasons may be the reduced bioavailability of the contaminant in the soil or sediment. In biomimetic approaches, such as solid phase micro-extraction (SPME) or measurements with C18-discs, the freely dissolved concentration in the (pore) water is determined. The SPME-fibre or C18-disc may serve as a surrogate organism, but sometimes underestimates, and sometimes overestimates bioavailability. The soil (or sediment) availability ratio (SARA) method, that uses organisms to study the uptake of freshly added and 'aged' chemicals, is proposed to study the magnitude of the reduction in bioavailability. SARA also includes the organism-specific exposure and depuration routes.
PT:  Journal-article
AN:  20001909483

Record 109 of 187 in CAB Abstracts 1998/08-2000/07

TI:  Determination of methyl tert-butyl ether in surface water by use of solid-phase microextraction.
AU:  Achten-C; Puttmann-W
SO:  Environmental-Science-and-Technology. 2000, 34: 7, 1359-1364; 41 ref.
LA:  English
AB:  A new method based on solid-phase microextraction (SPME) has been developed for the determination of methyl tert-butyl ether (MTBE) in surface water at sub-ppb concentrations. The combination of SPME and GC/MS can be applied for the detection of MTBE at low concentrations if limiting factors are optimized. Best results were obtained with a cooled (5oC) 75 µm poly(dimethylsiloxane)/Carboxen (PDMS/Carboxen, black) fibre at a sample temperature of 18-19oC and a sodium chloride concentration of 25%. Sixty minute extraction time showed the best compromise between time-consuming and effective extraction in a 1.5 ml vial filled with the water sample. The detection limit under the conditions of a defined signal-to-noise ratio of 10:1 is 10 ng/litre, and the relative standard deviation for replicate injections of spiked river water (10 ng/litre) was 12% (n=10). The use of MTBE as a fuel additive in Germany has led to detectable concentrations of 7-160 ng/litre in water of the Rhine, Elbe, Main, and Oder rivers. The median concentration (n=7) was 67 ng/L, and the maximum values were observed in the water of the Rhine. MTBE was also detected in rainwater precipitation in the centre of Frankfurt/Main at concentrations of 9 and 70 ng/L MTBE. The median concentrations of MTBE in streams and precipitation are six and two times lower compared to values measured in the USA, respectively. The data reflect the less intense use of MTBE in Germany in comparison to the USA.
PT:  Journal-article
AN:  20001911326

Record 110 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-S1496
TI:  Ethanol-modified subcritical water extraction combined with solid-phase microextraction for determining atrazine in beef kidney.
AU:  Curren-MSS; King-JW
PY:  2001
SO:  Journal-of-Agricultural-and-Food-Chemistry; 49 (5) 2175-2180, 34 ref.
DT:  Journal-Article
AB:  Determination of pesticide levels in food products has prompted the development of sensitive and rapid methods of analysis that are solvent-free or utilize solvents that are benign to the environment and laboratory worker.  In this study, a novel extraction method that utilizes ethanol-modified subcritical water in combination with solid-phase microextraction (SPME) was developed for the removal of atrazine from beef kidney.  In situ sample cleanup was achieved using matrix solid-phase dispersion.  A cross-linked polymer, XAD-7 HP, was utilized as a dispersing material for kidney samples.  Subcritical water extractions were performed with a pressurized solvent extraction unit at 100 degree C and 50 atm.  Experimental parameters investigated were vol. of solvent and amount of modifier required for complete extraction of atrazine and optimization of the extraction time.  It was found that 30% ethanol in water (v/v) was adequate for the complete extraction of atrazine.  A Carbowax-divinylbenzene SPME fibre was used to sample the aqueous extracts.  Analysis of fibre contents was by ion-trap GC MS utilizing the single ion mode.  Total time of analysis for a single kidney sample was 90 min.  Average percentage recoveries from samples spiked to concn. of 2 and 0.2 mug/g were 104 and 111, respectively; average relative s.d. were 10 and 9, respectively.  Detection limit for beef kidney spiked with atrazine was found to be 20 ng/g of sample.

Record 111 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-P1434
TI:  Solid-phase microextraction-mass spectrometry:  a new approach to the rapid characterization of cheeses.
AU:  Peres-C; Viallon-C; Berdague-JL
PY:  2001
SO:  Analytical-Chemistry; 73 (5) 1030-1036, 24 ref.
DT:  Journal-Article
AB:  This work describes a new method for the rapid characterization of cheeses by solid-phase microextraction coupled with MS (SPME-MS).  Volatile components were extracted from Camembert cheese samples using a Carboxen/PDMS 75 mum fibre placed for 10 min at 20 degree C in the headspace of the cheese.  The substances adsorbed were then transferred directly from the injector to the inlet of a mass spectrometer through a 1-m deactivated silica capillary column heated to 210 degree C.  The mass spectra thus obtained without prior chromatographic separation formed a `fingerprint' of the analysed sample.  For data analysis, the mass fragments of each spectrum (45 less than m/z less than 150 amu) were considered as potential descriptors of the composition of the headspace of the cheeses.  Stepwise discriminant analysis was used to select a limited number of mass fragments that afforded an operational classification of the batches of cheeses studied.  This new method offers the advantage of minimizing thermal, mechanical, and chemical modifications of the matrix, thereby reducing the risk of analytical artifacts.  It is concluded that SPME-MS provides a simple and effective approach to rapid quality control by analysis of the volatile fraction of foods.

Record 112 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-M1228
TI:  Changes in the volatile profile of oats induced by processing.
AU:  Sides-A; Robards-K; Helliwell-S; Min-An
PY:  2001
SO:  Journal-of-Agricultural-and-Food-Chemistry; 49 (5) 2125-2130, 11 ref.
DT:  Journal-Article
AB:  Effects of processing on the sensory properties and aroma compound profile of oats were investigated.  Samples of an Australian oat cv., Echidna, were processed on a pilot-scale.  At each stage of the processing (raw oats, groats, kiln dried dehulled (KDHO), and rolled (flaked)) samples were removed for later sensory analysis and GC-MS analysis of the flavour components.  Mean flavour panel scores from a trained panel were calculated according to attributes (cereal, burnt, toasted, floury and yeasty).  Attributes were generally similar for both KDHO and flaked oats except in the yeasty attributes.  Panelists were able to differentiate between groats, KDHO and flaked oats (raw oats were not included).  Largest effects of heat processing were found for the following attributes:  toasted and yeasty aroma; toasted, cereal and yeasty flavour; and toasted and yeasty aftertaste.  A multi-organoleptic sensor analyser was able to differentiate all samples when the output was subjected to discriminant function analysis.  A reintroduced sample was recognized with a confidence level greater than 96%.  Solid-phase microextraction (SPME) of headspace followed by GC-MS was used to identify volatiles after either dry or slurry heating.  Several SPME fibre types were evaluated as to their ability to sorb oat volatiles.  A 100-mum poly(dimethylsiloxane) SPME fibre was found to provide the best adsorption profile as measured by number of componds sorbed and peak area response.  A range of alcohols, aldehydes, alkyl benzenes, dienes and ketones was identified in the processed samples.

Record 113 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-H2268
TI:  Influence of packaging on the aroma stability of strawberry syrup during shelf life.
AU:  Ducruet-V; Fournier-N; Saillard-P; Feigenbaum-A; Guichard-E
PY:  2001
SO:  Journal-of-Agricultural-and-Food-Chemistry; 49 (5) 2290-2297, 18 ref.
DT:  Journal-Article
AB:  Use of different packaging types (glass, PVC and PET bottles) for preservation of aroma quality in a strawberry syrup (used to make a non-alcoholic beverage) during 0-350 days storage was investigated.  Levels of esters, alcohols and aldehydes in the syrup were analysed by solid-phase micro-extraction (SPME) and solvent extraction.  During storage, hydrolysis of esters in acids and alcohols led to a modification of the aroma profile which can be explained by the replacement of `fruity' and `fresh' notes by a `dairy note' in the syrup.  Aroma compounds that were responsible for fruit notes, such as methyl cinnamate, methyl anthranilate and methyl dihydrojasmonate, were strongly reduced after 90 days.  This could be explained by a selective interaction of these compounds with the packaging matrix (PET or PVC).  After 330 days, a significant decrease of the `fruity' notes occurred in PET packaging.  Results suggest that syrups packaged in PVC and glass bottles maintain a balanced aroma during long-term storage.

Record 114 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-H2267
TI:  Degradation of monoterpenes in orange juice by gamma radiation.
AU:  Xuetong-Fan; Gates-RA
PY:  2001
SO:  Journal-of-Agricultural-and-Food-Chemistry; 49 (5) 2422-2426, 36 ref.
DT:  Journal-Article
AB:  Effects of irradiation on volatile compounds and lipid oxidation in orange juice were studied.  Single-strength orange juice was irradiated with 0, 0.89, 2.24, 4.23, and 8.71 gGy of gamma-radiation at 5 degree C and then stored at 7 degree C for 21 days.  Volatile compounds, isolated by solid-phase microextraction (SPME), were separated and identified by GC with a mass selective detector.  The majority of the volatile compounds were terpenes, and the most abundant volatile compounds were ethanol and limonene.  Most volatile compounds were stable during the 21-day storage period except geranial and neral which decreased over time.  Irradiation reduced the concn. of acyclic monoterpenes, such as geranial, neral, myrcene and linalool, 1 and 7 days after irradiation, but did not affect other monoterpenes, sesquiterpenes, or other volatile compounds.  The reduction of acyclic monoterpenes increased linearly with radiation dose, and correlated with an increase in TBARS content.  Reduction in the concn. of monoterpenes induced by irradiation was not significant 21 days after irradiation.  Results indicate that acyclic monoterpenes are sensitive to irradiation whereas most other volatile compounds are resistant.

Record 115 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-H2180
TI:  Using HS-SPME to determine the effects of reducing insoluble solids on aromatic composition of orange juice.
AU:  Jordan-MJ; Tillman-TN; Mucci-B; Laencina-J
PY:  2001
SO:  Lebensmittel-Wissenschaft-und-Technologie; 34 (4) 244-250, 20 ref.
DT:  Journal-Article
AB:  Effects of reducing insoluble solids (IS) contents in orange juices on aroma compounds in headspace were determined, using juices collected from the outlet of the finisher device (10-15% IS) or the centrifuge (less than or equal3% IS); pulp samples were also collected from the centrifuge for analysis.  Solid-phase microextraction (SPME) using 2 fibre coatings (polar polyacrylate vs. nonpolar polydimethylsiloxane) was compared with simultaneous steam distillation-extraction (SDE) for aroma fraction analysis by GC-FID and GC-MS.  Alcohols, aldehydes, esters and ketones, and terpenic hydrocarbon fractions were determined.  Reducing IS reduced levels of all fractions except esters/ketones.  Reductions in aldehyde contents were more marked on SPME using the polar coating, whereas the nonpolar coating was better for detecting alterations in levels of alcohols and terpenic hydrocarbons.  SDE confirmed SPME results.

Record 116 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-H2148
TI:  Characterisation of grappa from autochthonous monovarietal Sicilian cultivars.
AU:  D'Agostino-S; Papucci-A; Agozzino-P; Avellone-G; Barbera-D
PY:  2001
SO:  Industrie-delle-Bevande; 30 (173) 238-243, 249, 22 ref.
DT:  Journal-Article
AB:  Grappa samples derived from marcs of autochthonous monovarietal grape cv. from Sicily were characterized.  3 grappa samples (over-ripened Zibibbo di Pantelleria suitable for Muscat production, Zibibbo sweetened with raisins and the semi-aromatic cv. Ansonica) were subjected to physicochemical analysis and volatile compound analysis using SPME followed by GC/MS.  Results showed that differences in the physicochemical and volatile compound analyses of each sample were correlated with either varietal differences of the grapes or with method of distillation.  It is suggested that use of SPME followed by GC/MS is a suitable method for examination of the aromatic quality of grappa.

Record 117 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-H2184
TI:  Optimization of headspace solid phase microextraction for analysis of wine aroma compounds.
AU:  Whiton-RS; Zoecklein-BW
PY:  2000
SO:  American-Journal-of-Enology-and-Viticulture; 51 (4) 379-382, 21 ref.
DT:  Journal-Article
AB:  Investigations conducted to optimize headspace solid phase microextraction (SPME) for isolation of aroma compounds from wines for subsequent analysis by GC-MS are described.  Trials were conducted on model solutions of typical wine aroma compounds, and on Pinot noir wine spiked with aroma compounds, using SPME fibres with a 65 mum Carbowax divinylbenzene coating (Supelco, Bellfonte, PA, USA).  Effects of sampling times, temp. and ethanol concn. were evaluated for the aroma compounds studied.  Sampling times up to 60 min and sample temp. 35 degree C increased sensitivity for low-volatility analytes, especially polar compounds, whereas lower temp. and shorter sampling times may be more appropriate for more volatile or non-polar compounds.  Recovery of most aroma compounds decreased with increasing ethanol concn.  Practical implications of these results for wine analysis are discussed.

Record 118 of 187 in FSTA Current 1990-2001/09

AN:  2001-09-H2087
TI:  Analysis of free fatty acids, higher alcohols and esters in ginjyo-shu produced in the northern part of Kyushu.
AU:  Utsunomiya-H; Yamada-O; Hashiguchi-T
PY:  2000
SO:  Journal-of-the-Brewing-Society-of-Japan-(Nippon-Jozokyokai-Shi); 95 (3) 214-218, 9 ref.
DT:  Journal-Article
AB:  Free fatty acids, higher alcohols and esters were determined by headspace SPME GC in 43 types of ginjyo-shu sake produced in the northern part of Kyushu (Fukuoka, Saga and Nagasaki districts).  Data are given for concn. of 3 higher alcohols, 3 acetates, 2 free fatty acids and 2 ethyl esters, together with correlations between these constituents.  Ethyl acetate showed strong negative correlations with concn. of caproic acid, caprylic acid and their ethyl esters.  Concn. of caproic and caprylic acids and those of their respective ethyl esters were strongly positively correlated.  Ginjyo-shu fermented with a cerulenin-resistant yeast mutant (with improved ethyl caproate productivity) showed increased contents of caproic acid and ethyl caproate, low ethyl acetate content and low caprylic acid/caproic acid ratio.

Record 119 of 187 in FSTA Current 1990-2001/09

AN:  2001-08-J1950
TI:  An SPME based method for the investigation of volatile compounds in spreading hazelnut creams.
AU:  Saba-A; Cuzzola-A; Raffaelli-A; Salvadori-P
PY:  2001
SO:  Italian-Food-&-Beverage-Technology; No. 23, 34-36, 4 ref.
DT:  Journal-Article
AB:  Hazelnut spreads contain cocoa, milk, hazlenuts and flavourings, all of which may provide volatile compounds contributing to the sensory properties of the product.  In this study, use of solid phase microextraction (SPME) techniques coupled with GC MS were investigated as methods for the characterization of volatile compounds present in hazelnut spreads.  Results showed that the optimum temp. for SPME was 50 degree C, using a fibre coated with polydimethylsiloxane (PDMS)/divinylbenzene (DVB) or DVB/carbowax/PDMS.  Some of the compounds found in a commercial hazelnut spread are listed.

Record 120 of 187 in FSTA Current 1990-2001/09

AN:  2001-08-H1923
TI:  Development of a SPME-GC-ECD methodology for selected pesticides in must and wine samples.
AU:  Correia-M; Delerue-Matos-C; Alves-A
PY:  2001
SO:  Fresenius'-Journal-of-Analytical-Chemistry; 369 (7/8) 647-651, 11 ref.
DT:  Journal-Article
AB:  Development of a method for determination of selected pesticide residues in musts and wines is related.  Pesticides selected were:  the fungicides, vinclozolin, procymidone, iprodione, penconazole, fenarimol, folpet, nuarimol and hexaconazole, the insecticide chlorpyriphos, and 2 acaricides, bromopropylate and tetradifom.  The method employed solid-phase microextraction together with a GC-electron capture detection system and required minimal sample preparation, i.e. dilution of the must or wine.  The assay was linear within the range 5-100 mug/l, a range that encompasses the proposed MRL for pesticide residues in wines, and measurements had an associated error (relative s.d.) of less than 20%.  The developed analytical technique was then used to determine selected pesticide residue concn. in Portuguese musts and wines.

Record 121 of 187 in FSTA Current 1990-2001/09

AN:  2001-08-H1924
TI:  Comparison of extraction techniques for gas chromatographic determination of volatile carbonyl compounds in alcohols.
AU:  Wardencki-W; Orlita-J; Namiesnik-J
PY:  2001
SO:  Fresenius'-Journal-of-Analytical-Chemistry; 369 (7/8) 661-665, 22 ref.
DT:  Journal-Article
AB:  Conventional solvent extraction and solid-phase microextraction techniques were compared for use in an assay for determination of carbonyl compounds in alcoholic beverages.  In the assay, carbonyl components, which may produce undesirable sensory properties in alcoholic beverages, are derivatized with o-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine to form oximes which are extracted and quantified using a GC-electron capture detection method.  Results determined that for oximes of up to 6 carbon atoms, detection limits with conventional liquid-liquid extraction and microextraction techniques were 0.23-3.3 and 0.005-0.33 mug/l, respectively.

Record 122 of 187 in FSTA Current 1990-2001/09

AN:  2001-08-B1168
TI:  Biotransformation of (R)-(+)- and (S)-(-)-limonene by fungi and the use of solid phase microextraction for screening.
AU:  Demyttenaere-JCR; Belleghem-K-van; Kimpe-N-de
PY:  2001
SO:  Phytochemistry-; 57 (2) 199-208, 25 ref.
DT:  Journal-Article
AB:  Sporulated surface cultures of 60 fungal strains were screened for bioconversion of (R)-(+)- and (S)-(-)-limonene.  Metabolites were assayed using a solid phase microextraction (SPME) headspace adsorption technique with GC quantification of volatiles.  Several Penicillium spp. produced (R)-(+)-alpha-terpineol from (R)-(+)-limonene, other bioconversion products included gamma-terpinene, terpinolene, alpha-phellandrene, endo-fenchol, menth-3-ene-1-ol, p-cymene, neo-dihydrocarveol, cis- and trans-limonene oxides, and perillyl alcohol.  Selected fungal strains were also grown in liquid culture for a more detailed examination of bioconversion volatiles; samples were monitored by dynamic headspace, steam distillation, solvent extraction and liquid-liquid extraction with GC, GC MS and NMR analyses.  P. digitatum converted (R)-(+)- and (S)-(+)-limonene to alpha-terpineol as the major metabolite, with yields of up to 100% after 8 h, but also produced some minor metabolites, including cis- and trans-p-menth-2-en-1-ol, neo-dihydrocarveol and limonene oxide.  Bioconversion of (R)-(+)- and (S)-(+)-limonene by Corynespora cassiicola produced (1S,2S,4R)- and (1R, 2R, 4S)-limonene-1,2-diol, respectively.  The limonene substrate was stable in fungal cultures despite the drop in pH with time.

Record 123 of 187 in FSTA Current 1990-2001/09

AN:  2001-08-A1483
TI:  Lipid analysis of PUFA in the new millennium and future trends.
AU:  Wada-S
PY:  2001
SO:  Journal-of-Oleo-Science; 50 (5) 329-338, 9 ref.
DT:  Journal-Article
AB:  Methods for analysis of PUFA are discussed with reference to:  instrumental analysis of PUFA (docosahexaenoic acid analysis by proton and C NMR, and analysis of triacylglycerol molecular species by LC-MS); lipid flavour compounds in fish oils and use of solid phase microextraction (SPME) for their analysis; and current `hot' topics in lipid research (CLA analysis and use of inositol hexaphosphate as an antioxidant in fish oils).  [This paper was originally presented at the Japan Oil Chemists' Society and American Oil Chemists' Society World Congress 2000 (JAWC 2000), held in Kyoto, Japan, Oct. 2000.]

Record 124 of 187 in FSTA Current 1990-2001/09

AN:  2001-07-J1653
TI:  Identification of volatile compounds in cantaloupe at various developmental stages using solid phase microextraction.
AU:  Beaulieu-JC; Grimm-CC
PY:  2001
SO:  Journal-of-Agricultural-and-Food-Chemistry; 49 (3) 1345-1352, 53 ref.
DT:  Journal-Article
AB:  An automated rapid headspace solid phase microextraction (SPME) method was used to extract volatile aroma and flavour compounds from cantaloupe melons (cv. Sol Real).  86 compounds already reported for muskmelons were recovered and an additional 53 compounds not previously reported were identified or tentatively identified.  The SPME method extracted a number of volatiles that could be used to differentiate clearly between var., growth stage, and stage of harvest ripeness.  Most of the newly reported compounds in the samples were esters and aldehydes that have already been demonstrated to be flavour-related compounds in other products.  All esters believed to have flavour impact increased progressively after pollination, and this trend continued with increasing harvest ripeness.  However, compound recovery often decreased when fruits were harvested over-ripe.  Most aldehydes increased during early growth stages and then tapered off with increasing harvest maturity.  It is concluded that the SPME method is suitable for recovering most compounds reported to impart characteristic flavour/aroma in muskmelons from canteloupe melons.  In addition, SPME offers experimental flexibility and the ability to discover more compounds and address flavour quality changes in fresh-cut cantaloupe.

Record 125 of 187 in FSTA Current 1990-2001/09

AN:  2001-07-H1756
TI:  Solid-phase microextraction determination of alcohol using pencil lead.
AU:  Zhan-Tong; Lu-Guanghan; Yao-Xin
PY:  2001
SO:  Analytical-Letters; 34 (4) 627-634, 10 ref.
DT:  Journal-Article
AB:  Due to problems associated with conventional coatings, use of pencil lead as a sorbent in solid phase microextraction (SPME) was investigated for GC-FID determination of alcohol in water.  In studies with isoamyl alcohol, the linear range of detection was 5 x 10---6 to 2.5 x 10---8 g/ml, and the detection limit was 5 x 10---9 g/ml.  Pencil lead also successfully enriched methanol, n-propanol, tertiary butyl alcohol and n-butanol.  The method was used for determination of isoamyl alcohol in spiked samples of tap water and lake water.  Recoveries of 96-107.6% were obtained.  It is concluded that pencil lead is a suitable material for use in SPME.

Record 126 of 187 in FSTA Current 1990-2001/09

AN:  2001-07-H1752
TI:  Comparison of polyphenols and aroma in red wines from Portuguese mainland versus Azores Islands.
AU:  Baptista-JAB; Tavares-JFda-P; Carvalho-RCB
PY:  2001
SO:  Food-Research-International; 34 (4) 345-355, 34 ref.
DT:  Journal-Article
AB:  Polyphenolic compounds (resveratrol, piceid and quercetin) and volatile aroma compounds were analysed in Azorean red wines, as affected by climate, soil composition (basaltic) and viticulture, and as compared with mainland Portuguese red wines.  RP-HPLC-UV and headspace solid phase microextraction-GC were used in analyses.  Mean values for 9 Portuguese and 3 Azorean wines were as follows (mg/l):  trans-piceid 2.58 and 1.96; cis-piceid 0.31 and 0.18; trans-resveratrol 1.56 and 3.36; cis-resveratrol 0.30 and 0.83; and quercetin 4.38 and 5.57.  Concn. of stilbeness appeared to vary according to grape var., but exogenous factors were also significant.  Aroma profiles of wines from the different regions varied considerably (results tabulated), although ethyl hexanoate was consistently the most abundant compound, followed by phenylethyl alcohol.

Record 127 of 187 in FSTA Current 1990-2001/09

AN:  2001-07-H1676
TI:  Solid-phase microextraction for the enantiomeric analysis of flavors in beverages.
AU:  Ebeler-SE; Sun-GM; Datta-M; Stremple-P; Vickers-AK
PY:  2001
SO:  Journal-of-AOAC-International; 84 (2) 479-485, 22 ref.
DT:  Journal-Article
AB:  Solid-phase microextraction combined with gas chromatographic/mass spectrometric analysis and separation on a chiral cyclodextrin stationary phase was used to analyse the composition of chiral aroma compounds in flavoured alcoholic beverages.  Several enantiomeric terpenes, esters, alcohols, norisoprenoids and lactones were identified in berry-, peach-, strawberry-, and citrus-flavoured wine and malt beverages (wine coolers).  Using this technique, it was possible to confirm the addition of synthetic flavouring to several beverages, consistent with label designations.  It is concluded that the method provides a simple and rapid means of profiling chiral aroma compounds in flavoured alcoholic beverages.

Record 128 of 187 in FSTA Current 1990-2001/09

AN:  2001-07-F0288
TI:  Determination of plastic monomers in water by solid-phase microextraction coupled with liquid chromatography.
AU:  Batlle-R; Sanchez-C; Nerin-C
PY:  2001
SO:  Journal-of-AOAC-International; 84 (2) 431-436, 25 ref.
DT:  Journal-Article
AB:  A method is presented for the determination of 2 major plastic monomers, terephthalic acid and vinyl acetate, which are widely used to manufacture plastics that come in contact with foods.  The analytes are extracted from aqueous solutions using solid-phase microextraction, followed by quantitation by LC with UV detection.  Multivariate optimization was applied.  The optimized method showed linear ranges of 5-150 mug/g for terephthalic acid and 7.5-100 mug/g for vinyl acetate.  Coeff. of variation at a spiking level of 20 mug/g were 13.6% for terephthalic acid and 3.1% for vinyl acetate; detection and quantitation limits were 0.59 and 1.99 mug/g, respectively, for terephthalic acid and 1.56 and 5.20 mug/g, respectively, for vinyl acetate.  The characteristics of both the extraction technique and its coupling with LC are described and discussed.

Record 129 of 187 in FSTA Current 1990-2001/09

AN:  2001-07-A1148
TI:  Flavor threshold for acetaldehyde in milk, chocolate milk, and spring water using solid phase microextraction gas chromatography for quantification.
AU:  Aardt-M-van; Duncan-SE; Bourne-D; Marcy-JE; Long-TE; Hackney-CR; Heisey-C
PY:  2001
SO:  Journal-of-Agricultural-and-Food-Chemistry; 49 (3) 1377-1381, 22 ref.
DT:  Journal-Article
AB:  Flavour thresholds for acetaldehyde were determined for whole, low-fat, and skim milks, chocolate-flavoured milk, and spring water using an untrained sensory panel.  Knowledge of the acetaldehyde threshold is important because acetaldehyde forms in milk during storage as a result of light oxidation and also as a degradation product during the melt processing of PET, a relatively new packaging choice for milk and water.  There was no significant difference in the acetaldehyde threshold in milk of various fat contents, with thresholds ranging from 3939 to 4040 ppb.  Chocolate-flavoured milk and spring water showed thresholds of 10 048 and 167 ppb, respectively, which compare favourably with previous studies.  Solid phase microextraction (SPME) was verified as an effective method for the recovery of acetaldehyde in all media with detection levels as low as 200 and 20 ppb in milk and water, respectively, when using a polydimethyl siloxane/Carboxen SPME fibre in static headspace at 45 degree C for 15 min.

Record 130 of 187 in FSTA Current 1990-2001/09

AN:  2001-06-T0537
TI:  Volatile components in persimmon vinegars by solid-phase microextraction.
AU:  Ji-Hyung-Seo; Nan-Young-Park; Yong-Jin-Jeong
PY:  2001
SO:  Korean-Journal-of-Food-Science-and-Technology; 33 (1) 153-156, 13 ref.
DT:  Journal-Article
AB:  Traditional static headspace and headspace solid-phase microextraction (SPME) techniques were compared for efficacy in extraction of flavour compounds from persimmon vinegar headspace; extracts were analysed by GC-FID.  SPME was conducted at 80 degree C for 20 min.  Total peak area, as calculated from chromatograms was 18.18 x 10-6 by SPME-GC and 1.35 x 10-6 by static headspace GC, representing a total of 34 and 21 identified compounds, respectively.  Major volatile compounds identified were acetic acid, ethyl acetate, 3-hydroxy-2-butanone, ethanol and phenethyl alcohol.  SPME-GC identified 6 acids, 7 aldehydes, 6 alcohols, 9 esters, 2 hydrocarbons, 1 ketone and 3 other compounds.  The proportions of benzaldehyde, phenethylacetate and phenethylalcohol in SPME extracts were higher than those in extracts prepared using static techniques.

Record 131 of 187 in FSTA Current 1990-2001/09

AN:  2001-06-R0450
TI:  Speciation of organotins in environmental samples by SPME-GC:  comparison of four specific detectors:  FPD, PFPD, MIP-AES and ICP-MS.
AU:  Aguerre-S; Lespes-G; Desauziers-V; Potin-Gautier-M
PY:  2001
SO:  Journal-of-Analytical-Atomic-Spectrometry; 16 (3) 263-269, 39 ref.
DT:  Journal-Article
AB:  Performances of 4 specific detectors used for speciation of butyl- and phenyltin compounds after solid phase microextraction (SPME) and GC separation were evaluated.  A flame photometric detector (FPD), a pulsed flame photometric detector (PFPD), a microwave induced plasma atomic emission spectrometer (MIP-AES) and ICP-MS were used.  The principle of PFPD, a new generation of FPD, is presented.  The original transfer line used between GC and ICP-MS is detailed.  High SPME preconcentration allowed very low limits of detection (LOD) to be reached ( less than 500 pg l---1 Sn for all detectors).  Sensitivity, linearity and selectivity of the different detectors are also discussed.  As expected, ICP-MS is the most sensitive (LOD 0.6-20 pg l---1 Sn), but the cheapest PFPD was also of significant interest.  The analytical procedure was applied to determination of organotins in 2 reference materials:  sediment (PACS 2) and fish tissue (NIES 11).  These different examples show that the detection of ultra-trace tin species is now possible in natural samples using a combination of SPME and GC with a specific detector.

Record 132 of 187 in FSTA Current 1990-2001/09

AN:  2001-06-J1283
TI:  Characterisation of `Galia' melon aroma by GC and mass spectrometric sensory measurements after prolonged storage.
AU:  Fallik-E; Alkali-Tuvia-S; Horev-B; Copel-A; Rodov-V; Aharoni-Y; Ulrich-D; Schulz-H
PY:  2001
SO:  Postharvest-Biology-and-Technology; 22 (1) 85-91, 14 ref.
DT:  Journal-Article
AB:  Effect of storage (4 degree C for 15 days followed by 20 degree C for 4 days) on the development of aroma compounds in 2 cv. (C8 and 5080) of Galia melons (Cucumis melo var. reticulans) was investigated, in an attempt to find the optimal stage of maturity for harvesting these fruits.  A new and rapid GC-MS method coupled with solid phase microextraction (SPME) sampling was used to analyse aroma volatiles in melons; results were compared with common quality parameters (firmness, colour, total soluble solids).  Results showed that although C8 melons had higher aroma volatiles content than 5080 melons, 5080 melons had a longer shelf life, were firmer and had a higher sugar content than C8 melons, thus increasing their consumer acceptability.  During maturation of fruit in storage, the concn. of aroma volatiles were observed to increase when the melon peel turned from green to light yellow.  Hence, it is suggested that fruit should be harvested when the peel is light yellow in colour with green patches in order obtain desirable aroma levels in melons following prolonged storage.

Record 133 of 187 in FSTA Current 1990-2001/09

AN:  2001-06-H1503
TI:  Statistical evaluation of aroma and metal content in Tokay wines.
AU:  Muranyi-Z; Kovacs-Z
PY:  2000
SO:  Microchemical-Journal; 67 (1/3) 91-96, 10 ref.
DT:  Journal-Article
AB:  Composition of aroma compounds and metals in wines from the Tokay region of Hungary was determined using SPME.  Data were than analysed using a multi-variable statistical approach to investigate their relationship with characteristics such as grape var., area of origin and wine vintage.  Five wine var. (Muskotaly, Aszu, Szamorodni dry, Szamorodni sweet and Furmint) were analysed.  Composition of aroma compounds was similar in wines having similar sensory characteristics and was significantly influenced by area of origin.  Results indicated that growing area, type and var. all have a strong influence on the qualitative and quantitative composition of metals and aroma compounds in wines.

Record 134 of 187 in FSTA Current 1990-2001/09

AN:  2001-06-H1354
TI:  Monitoring ester formation in grape juice fermentations using solid phase microextraction coupled with gas chromatography-mass spectrometry.
AU:  Vianna-E; Ebeler-SE
PY:  2001
SO:  Journal-of-Agricultural-and-Food-Chemistry; 49 (2) 589-595, 36 ref.
DT:  Journal-Article
AB:  Volatile esters contribute important floral and fruity sensory properties to wine.  Numerous factors influence the biosynthesis and hydrolysis of esters throughout yeast fermentation; however, methods to monitor the dynamic changes in ester production that occur during winemaking processes are limited.  In this study, it is shown that solid phase microextraction (SPME), a rapid, solventless sampling procedure, combined with GC/MS analysis is a useful method for the nearly continuous analysis of volatile compounds such as esters that are produced during fermentation.  Accuracy, precision, and limits of quantification were comparable to those of other sample preparation methods such as liquid-liquid extraction.  Using GC/MS-SPME to monitor fatty acid ethyl esters and acetate esters, detailed information ws obtained on the production patterns of ester formation during fermentation.  This method now enables the monitoring of volatiles during fermentation and can provide greater insight into yeast metabolism and flavour formation.

Record 135 of 187 in FSTA Current 1990-2001/09

AN:  2001-05-T0427
TI:  Chemical composition of the essential oil and headspace solid-phase microextraction of the guava fruit (Psidium guajava L.).
AU:  Paniandy-JC; Chane-Ming-J; Pieribattesti-JC
PY:  2000
SO:  Journal-of-Essential-Oil-Research; 12 (2) 153-158, 25 ref.
DT:  Journal-Article
AB:  Essential oil and headspace of fresh guava fruits (Psidium guajava L.) from trees grown on the island of Reunion were obtained by steam hydrodistillation and headspace solid-phase microextraction (SPME), respectively.  Composition of the extract was investigated by GC and GC-MS.  73 compounds were identified, 61 by hydrodistillation and 24 by headspace SPME.  In the headspace, major constituents were:  hexanal (65.9%), gamma-butyrolactone (7.6%), (E)-2-hexenal (7.4%), (E,E)-2,4-hexadienal (2.2%), (Z)-3-hexenal (2.0%), (Z)-2-hexenal (1.0%), (Z)-3-hexenyl acetate (1.3%) and phenol (1.6%); beta-caryophyllene (24.1%), nerolidol (17.3%), 3-phenylpropyl acetate (5.3%) and caryophyllene oxide (5.1%) were the major volatile constituents present in the hydrodistilled oil.  The study identified many compounds not previously reported in guava, such as gamma-butyrolactone (7.6%) in headspace SPME and nerolidol (17.6%) in the essential oil.  In addition, some compounds such as (Z)-3-hexenal, (E,E)-2,4-hexadienal, gamma-butyrolactone, borneol, phenol, cuminyl alcohol could be identified only using the headspace method.

Record 136 of 187 in FSTA Current 1990-2001/09

AN:  2001-05-P0893
TI:  Effects of milk fat, cocoa butter, or selected fat replacers on flavor volatiles of chocolate ice cream.
AU:  Welty-WM; Marshall-RT; Gruen-IU; Ellersieck-MR
PY:  2001
SO:  Journal-of-Dairy-Science; 84 (1) 21-30, 26 ref.
DT:  Journal-Article
AB:  Selected volatile flavour compounds of chocolate ice creams containing 0.6, 4.0, 6.0 or 9.0% milk fat or containing 2.5% milk fat, cocoa butter or 1 of 3 fat replacers (Simplesse, Dairy Lo or Oatrim) were analysed by GC and GC-MS using headspace solid-phase microextraction.  The headspace concn. of most of the selected volatile compounds increased with decreasing milk fat concn.  Fat replacers generally increased the concn. of volatiles found in the headspace compared with milk fat or cocoa butter.  Few differences in flavour volatiles were found between ice cream containing milk fat and ice cream containing cocoa butter.  Among the selected volatiles, 2,5-dimethyl-3(2-methyl propyl) pyrazine concn. was the most highly correlated (negatively) with milk fat concn., and it best discriminated among ice creams containing milk fat, cocoa butter or one of the fat replacers.

Record 137 of 187 in FSTA Current 1990-2001/09

AN:  2001-05-P0866
TI:  Use of preconcentration techniques applied to a MS-based `electronic nose'.
AU:  Schaller-E; Zenhaeusern-S; Zesiger-T; Bosset-JO; Escher-F
PY:  2000
SO:  Analusis-; 28 (8) 743-749, 6 ref.
DT:  Journal-Article
AB:  Four Swiss Emmental cheeses from 4 different factories were analysed with an electronic nose based on a MS detector, the SMart NoseRegistered.  3 sampling methods (non-preconc. static headspace, purge-and-trap and solid phase microextraction (SPME)) were compared in order to discriminate cheese ripeness.  Use of a preconcn. technique was found to be helpful, allowing extraction of volatile compounds with higher molecular masses, with SPME being the best method because of its better repeatability, its simplicity and its compatibility with an autosampler.

Record 138 of 187 in FSTA Current 1990-2001/09

AN:  2001-05-N0388
TI:  Investigation of olive oil volatile fraction by headspace SPME-GC/MS.
AU:  Mazzini-F; Barsanti-C; Saba-A; Raffaelli-A; Pucci-S; Salvadori-P
PY:  2000
SO:  Italian-Food-&-Beverage-Technology; No. 21, 32-34
DT:  Journal-Article
AB:  Use of headspace solid-phase microextraction (SPME) coupled with GC MS to characterize volatile compounds present in olive oil was investigated.  Optimal fibre type and extraction time and temp. were established and used to monitor 8 olive oil samples from 2 different Italian regions.  Max. extraction efficiency of volatile compounds was obtained using a Carbowax/DVB fibre for 20 min.  Although different volatile compounds had different optimum extraction temp., 40 degree C was found to be a suitable compromise temp. for multicomponent analysis.  When these conditions were used to analyse the 8 olive oil samples, 6 different volatile compounds were identified and the influence of sample origin on relative amounts of these compounds was clearly evident.

Record 139 of 187 in FSTA Current 1990-2001/09

AN:  2001-05-M0538
TI:  Screening for 2-acetyl-1-pyrroline in the headspace of rice using SPME/GC-MS.
AU:  Grimm-CC; Bergman-C; Delgado-JT; Bryant-R
PY:  2001
SO:  Journal-of-Agricultural-and-Food-Chemistry; 49 (1) 245-249, 9 ref.
DT:  Journal-Article
AB:  Solid phase microextraction (SPME) can be used to collect and concentrate compounds in the headspace of rice.  This study describes optimization parameters of temp., moisture and sampling time for this process.  Optimization was based upon the recovered levels of 2-acetyl-1-pyrroline (2-AP), which is responsible for the popcorn aroma in aromatic rice.  The method uses a sampling temp. of 80 degree C and adds 100 mul of water to 0.75 g of rice.  Rice is preheated for 25 min and a carboxen/DVB/PDMS SPME fibre is exposed to the headspace for 15 min; subsequent GC-MS analysis takes 35 min.  Samples of rice can be analysed as flour, milled kernels or brown rice.  21 experimental rice var. were analysed by the SPME method and results were compared with those obtained using a wet technique.  Recoveries of several ng of 2-AP from 0.75 g samples of aromatic rice were observed, whereas only trace amounts of 2-AP were recovered from nonaromatic rice.  Recovery from a single SPME headspace analysis was calculated to be 0.3% of the total 2-AP in the sample.

Record 140 of 187 in FSTA Current 1990-2001/09

AN:  2001-05-M0660
TI:  Analysis of headspace compounds of distillers grains using SPME in conjunction with GC/MS and TGA.
AU:  Biswas-S; Staff-C
PY:  2001
SO:  Journal-of-Cereal-Science; 33 (2) 223-229, 16 ref.
DT:  Journal-Article
AB:  Solid phase microextraction combined with GC-MS and thermogravimetric analysis (TGA) was used to analyse headspace compounds in distillers grains (dryer feed (DF) and distillers dried grains (DDG)).  SPME was conducted using a fused silica fibre coated with polydimethylsiloxane; this fibre was exposed to the headspace above samples for 1-2 h.  The fibre was then desorbed in the GC-MS injection port for separation and identification of compounds.  Up to 64 compounds were eluted from the GC column; higher numbers of compounds were exhibited by DF.  TGA was performed on samples to study their oxidative stability and volatile compounds evolved during heating.  Results indicated that SPME in conjunction with GC-MS and TGA provides a rapid and convenient means of determining volatile and semi-volatile compounds in distillers grains' headspace.  SPME was able to separate long chain fatty acid components, which is a multiple-step procedure using conventional methods.  TGA revealed many important aspects of drying temp. of distillers grains; it was determined that heating and drying grains at temp. greater than 250-300 degree C would result in degradation.  Differences in composition between unheated and heated grains and between DF and DDG are discussed.

Record 141 of 187 in FSTA Current 1990-2001/09

AN:  2001-05-H1002
TI:  Automated in-tube solid phase microextraction coupled with HPLC-ES-MS for the determination of catechins and caffeine in tea.
AU:  Jingcun-Wu; Wei-Xie; Pawliszyn-J
PY:  2000
SO:  Analyst-; 125 (12) 2216-2222, 40 ref.
DT:  Journal-Article
AB:  A polypyrrole (PPY) coated capillary and several commercially available capillaries (capillary GC columns) were compared with respect to their extraction efficiencies for catechins [-)-epigallocatechin, (+)-catechin, (-)-epicatechin, (-)-epigallocatechin gallate and (-)-epicatechin gallate) and caffeine.  Compared with commercial capillaries currently used for in-tube solid phase microextraction (SPME), the PPY coated capillary showed better extraction efficiency for all compounds studied.  Electrospray MS (ES-MS) detection conditions were also investigated.  After optimization of extraction and detection conditions, a method for sensitive and selective determination of catechins and caffeine was developed by coupling PPY coated capillary in-tube SPME with HPLC-ES-MS.  Catechins could be determined in both positive and negative ion detection modes.  The detection limit (S/N = 3) for each of the catechins was less than 0.5 ng ml---1.  Caffeine could be determined under positive ES-MS detection conditions only and its detection limit was 0.01 ng ml---1.  Caffeine and the 5 catechins were determined in several (green, black, oolong and herb) tea samples using the developed method.  Small amounts of catechins were also detected in grape juice and wine samples.

Record 142 of 187 in FSTA Current 1990-2001/09

AN:  2001-04-T0363
TI:  Analysis of the volatile components in vanilla extracts and flavorings by solid-phase microextraction and gas chromatography.
AU:  Sostaric-T; Boyce-MC; Spickett-EE
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (12) 5802-5807, 11 ref.
DT:  Journal-Article
AB:  Development and application of a solid-phase microextraction (SPME) method for qualitative analysis of vanilla extracts and flavourings was studied for use in conjunction with GC-MS.  Vanilla samples used included certified Bourbon, Indonesian and Tahitian vanilla flavourings, nature identical and synthetic vanilla flavourings and vanilla flavoured foods (yoghurt, ice cream, custard powder).  The optimized SPME sampling parameters for determination of the volatile components included poly(acrylate) fibre, 40-min sampling time at room temp., and 2-min desorption time.  Reproducibility of the method was good, with relative s.d. between 2.5 and 6.4% for the target compounds.  Data suggest that the origin of natural extracts can be readily determined from the GC profile and that differences exist between nature-identical and synthetic flavourings and natural extracts.  The method also has potential for identifying the type of vanilla extract/flavouring used to flavour food.

Record 143 of 187 in FSTA Current 1990-2001/09

AN:  2001-04-T0361
TI:  Production of yarrow (Achillea millefolium L.) in Norway:  essential oil content and quality.
AU:  Rohloff-J; Skagen-EB; Steen-AH; Iversen-TH
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (12) 6205-6209, 25 ref.
DT:  Journal-Article
AB:  Monoterpene and sesquiterpene contents of essential oils produced from yarrow (Achillea millefolium L.) were investigated at various stages of growth (vegetative, early bloom, full bloom).  Oils were extracted by steam distillation followed by GC or solid phase microextraction (SPME) with GC-MS analysis.  Essential oil content of plants was 0.13 and 0.34% at the vegetative and full bloom stages, respectively.  The ratio of monoterpenes to sesquiterpenes was 2:1 in the vegetative stage and 3:1 in the full bloom stage.  Levels of the monoterpenes alpha- and beta-pinene and alpha-thujone increased with increasing maturity, whereas levels of sabinene, camphor, borneol and bornyl acetate decreased.  Markedly higher amounts of sabinene and 1,8-cineole were detected in SPME samples than in oils obtained by steam distillation.  Similarly, significant amounts of sesquiterpenes, including beta-bisabolene, delta-cadinene, alpha-bisabolol and (Z,E)-farnesol were detected in SPME samples.

Record 144 of 187 in FSTA Current 1990-2001/09

AN:  2001-04-N0302
TI:  Mechanism of volatile compound production during storage of sunflower oil.
AU:  Keszler-A; Kriska-T; Nemeth-A
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (12) 5981-5985, 25 ref.
DT:  Journal-Article
AB:  Volatile compounds formed by thermal decomposition of hydroperoxides during storage of sunflower oil were analysed by headspace solid-phase microextraction sampling followed by GC MS.  The role of alkoxyl radicals was investigated using electron spin resonance.  On the basis of analytical results, reaction networks and mechanisms were constructed by computer modelling to describe formation of volatile products by radical decomposition of hydroperoxides.  It was found that aliphatic aldehyde products responsible for the off-flavour of sunflower oil originated from only 1 type of intermediate, the alkoxyl radical derived from the trigliceride of linoleic acid.

Record 145 of 187 in FSTA Current 1990-2001/09

AN:  2001-04-H0720
TI:  Caffeine determination in beverages by SPME and GC-MS.
AU:  Guidotti-M; Panzironi-L
PY:  2000
SO:  Industrie-delle-Bevande; 29 (170) 595-597, 605, 7 ref.
DT:  Journal-Article
AB:  Use of solid phase microextraction and GC-MS to determine levels of caffeine in tea and coffee samples was investigated.  The method was rapid, repeatable and showed good sensitivity, with a detection limit of 3 mug/l; relative s.d. was 10.9%.

Record 146 of 187 in FSTA Current 1990-2001/09

AN:  2001-04-A0676
TI:  Methodology for analysis of the volatile constituents of flavour.
AU:  Thomazini-M; Franco-MRB
PY:  2000
SO:  Boletim-da-Sociedade-Brasileira-de-Ciencia-e-Tecnologia-de-Alimentos; 34 (1) 52-59, 41 ref.
DT:  Review
AB:  Techniques for analysing the volatile compounds in foods that are responsible for food flavour are reviewed with reference to: methods for extraction (distillation-extraction, static and dynamic headspace analysis, solid phase microextraction); methods for separation (GC, capillary GC, GC-olfactometry, column chromatography-olfactometry (aroma extract dilution analysis and combined hedonic reponse measurement)); and use of GC-MS for identification of volatile compounds.

Record 147 of 187 in FSTA Current 1990-2001/09

AN:  2001-04-A0547
TI:  Measurement by SPME without chromatographic separation, a new analytical dimension.
AU:  Luisier-JL; Villettaz-JC; Azodanlou-R; Amado-R
PY:  2000
SO:  Mitteilungen-aus-Lebensmitteluntersuchung-und-Hygiene; 91 (6) 690-699, 9 ref.
DT:  Journal-Article
AB:  A method for determination of volatile compounds in foods is described, based on volatile adsorption using solid phase microextraction (SPME) and direct injection into a GC detector without preliminary chromatographic separation.  Applications using different detectors are presented, including:  use of FID to study the enzymic hydrolysis of amygdalin in water; use of FID for determination of hydrocarbon concn. in water samples; use of an NP detector for assessing the freshness of fish; and MS detection for the analysis of volatile compounds in Artemisia genepi essential oils.

Record 148 of 187 in FSTA Current 1990-2001/09

AN:  2001-03-J0521
TI:  Analysis of the aroma compounds of the pulp of Borassus aethiopium L. (Palmae) from Cameroon using GC-MS, SPME-GC-MS and olfactometry.
AU:  Jirovetz-L; Buchbauer-G; Ngassoum-MB
PY:  2000
SO:  Ernaehrung-; 24 (4) 159-161, 6 ref.
DT:  Journal-Article
AB:  Aroma compounds of pulp of fruit of the palm Borassus aethiopum, grown in Cameroon, were determined by GC-FID, GC-MS, solid phase microextraction (SPME)-MS and olfactometry.  Samples of B. aethiopum fruit essential oil, headspace and SPME extract were analysed.  greater than or equal40 volatiles could be detected.  Predominant components of the essential oil were limonene (62%), ethyl butanoate (10.1%), beta-pinene (6.6%), ethyl acetate (6.1%) and gamma-terpinene (5.3%).  Predominant constituents of the headspace included limonene (24.6%), ethyl hexanoate (17.4%), beta-pinene (11.4%), ethyl acetate (9.6%) and gamma-terpinene (7.8%).  Predominant constituents of the SPME extract included ethyl butanoate (49.1%), limonene (12.1%), ethyl acetate (9.4%), ethyl hexanoate (6.5%) and acetaldehyde (5.9%).

Record 149 of 187 in FSTA Current 1990-2001/09

AN:  2001-03-J0560
TI:  Solid-phase microextraction coupled with high performance liquid chromatography:  a complementary technique to solid-phase microextraction-gas chromatography for the analysis of pesticide residues in strawberries.
AU:  Zhi-Wang; Hennion-B; Urruty-L; Montury-M
PY:  2000
SO:  Food-Additives-and-Contaminants; 17 (11) 915-923, 14 ref.
DT:  Journal-Article
AB:  Solid-phase microextraction coupled with HPLC for the analysis of methiocarb, napropamide, fenoxycarb and bupirimate residue levels in strawberries.  Frozen strawberry samples were spiked with 125-200 mul of mixed standard solutions, containing 0.01-0.25 mg/ml of each compound, defrosted, blended, mixed with water and centrifuged.  An aliquot of the resulting supernatant was subjected to solid-phase microextraction (SPME) on a 60 mum polydimethylsiloxane/divinylbenzene fibre for 45 min at room temp.  Extracted pesticides on the SPME fibre were desorbed into the SPME/HPLC interface for HPLC analysis using acetonitrile water (55:45 (v/v)) as mobile phase, with diode-array detection at 205 and 240 nm.  The method was organic solvent-free for the whole extraction process and was found to be simple and easy to manipulate.  Detection limits were in the ranges 10-50 and 12-50 mug/kg at 205 and 240 nm, respectively, and the linear response covered the range from 0.05 to 2 mg/kg of pesticides in strawberries with regression coeff. greater than 0.99.  Relative s.d. ranged from 2.92-9.25% at 205 nm, for strawberry samples spiked with 0.5 mg/kg pesticide.

Record 150 of 187 in FSTA Current 1990-2001/09

AN:  2001-02-H0392
TI:  1999-2000 report of the Technical Committee.
AU:  Nyarady-S; Bendiak-D; Dull-CL; Murphey-J; Schwarz-P; Casey-G
CA:  American Society of Brewing Chemists Inc.
PY:  2000
SO:  Journal-of-the-American-Society-of-Brewing-Chemists; 58 (4) 175-176
DT:  Report
AB:  This 1999-2000 report of the ASBC Technical Committee covers activities of subcommittees on:  coordination of new and alternate methods of analysis; soluble starch; selective measurement of acetohydroxy acid precursors of vicinal diketones; evaluation of swab surface hygiene testing using ATP bioluminescence; assessment of malt grind by standard sieve tests; headspace solid phase microextraction for evaluation of hop essential oil components; assessment of beer colour by tristimulus analysis; citrate-buffered methylene violet stain for yeast viability; and application of nitrogen-purging of malt extracts to measure 2 dimethyl sulphide precursors by headspace GC.

Record 151 of 187 in FSTA Current 1990-2001/09

AN:  2001-02-H0366
TI:  Headspace solid-phase microextraction for determination of hop essential oils.
AU:  Kenny-S; Barber-L; Hill-P; Pruneda-T; Smith-R; Tinginys-A; Murphey-J
CA:  American Society of Brewing Chemists Inc.
PY:  2000
SO:  Journal-of-the-American-Society-of-Brewing-Chemists; 58 (4) 180-183, 3 ref.
DT:  Journal-Article
AB:  Comparative studies were conducted on analysis of hop essential oils by steam distillation-GC or headspace solid phase microextraction (SPME)-GC.  4 sample pairs of hop pellets were sent to collaborators; results were received from 6 laboratories.  Results are presented for humulene/caryophyllene (H/C), farnesene/caryophyllene (F/C) and farnesene/humulene (F/H) ratios.  For the H/C ratio, repeatability and reproducibility coeff. of variation with steam distillation were 0.4-3.2% and 1.4-13.0%, and were judged acceptable; with SPME, values were 2.5-10.1 and 3.3-10.1%, and were judged acceptable.  For the F/C ratio, repeatabilty and reproducibility coeff. of variation with steam distillation were 0.8-7.0 and 10.1-16.1% and were judged acceptable; values with SPME were 12.2-12.8% and 18.9-20.4%, of which repeatability was judged acceptable but reproducibility unacceptable.  For F/H ratio, repeatability and reproducibility coeff. of variation with steam distillation were 1.7-5.3 and 6.5-22.2%, of which repeatability was judged acceptable but reproducibility unacceptable; values with SPME were 8.1-9.3% and 16.6-30.8%, and were judged unacceptable.

Record 152 of 187 in FSTA Current 1990-2001/09

AN:  2001-02-H0476
TI:  The determination of benzoic acid in lemon flavored beverages by stir bar sorptive extraction-CGC-MS.
AU:  Tredoux-AGJ; Lauer-HH; Heideman-T; Sandra-P
PY:  2000
SO:  HRC-; 23 (11) 644-646, 10 ref.
DT:  Journal-Article
AB:  Stir bar sorptive extraction (SBSE), a recently introduced solventless extraction technique, was applied for enrichment and determination of benzoic acid in lemon flavoured beverages (soft drinks and lemon flavoured herb tea).  The stir bar is covered with 50 mg polydimethylsiloxane (PDMS) and the extraction mechanism is similar to that of solid phase microextraction (SPME), with an enrichment factor approx. 100x higher.  SBSE is followed by thermal desorption (TD)-capillary gas chromatography (CGC)-mass spectroscopy (MS).  Calibration graphs for benzoic acid were linear from 1 to 1000 p.p.m. for water and diluted soft drinks, and repeatability (n = 6) was less than 5% RSD.  SBSE also proved successful in analysis of flavour compounds in lemon flavoured beverages.

Record 153 of 187 in FSTA Current 1990-2001/09

AN:  2001-02-C0129
TI:  Methods for routine analysis of phthalates in food and environment.
AU:  Baerwinkel-D; Haufe-J; Kroh-LW
PY:  2000
SO:  Deutsche-Lebensmittel-Rundschau; 96 (11) 411-417, 8 ref.
DT:  Journal-Article
AB:  Studies were conducted on determination of phthalates in high fat foods (meat products, trout fillets, milk, cream, margarine or salad oil), drinking water and seep water from waste tips by GC-MS or GC-FID, after solid phase extraction (SPE) or solid phase microextraction (SPME).  Samples were analysed for dimethyl-, diethyl-, dibutyl-, butylbenzyl-, diethylhexyl- and dioctylphthalates.  Both SPE and SPME were suitable for sample preparation for phthalate analysis.  Diethylhexylphthalate was generally the main phthalate fraction present.  Mean total phthalate concn. in drinking water was 11.2 mug/l (range 3-22 mug/l).  The high-fat food samples studied had total phthalate concn. of 0.3  mg/kg (milk) to 2.4 mg/kg (salad oil).  Relative concn. of phthalate fractions differed between the foods studied.  Phthalate concn. in seep water from 2 general waste tips and a plastics industry waste tip, indicated that seep water from waste tips may be a source of contamination of the environment (including ground water) with phthalates.

Record 154 of 187 in FSTA Current 1990-2001/09

AN:  2001-01-T0025
TI:  Headspace sorptive extraction (HSSE) in the headspace analysis of aromatic and medicinal plants.
AU:  Bicchi-C; Cordero-C; Iori-C; Rubiolo-P; Sandra-P
PY:  2000
SO:  HRC-; 23 (9) 539-546, 10 ref.
DT:  Journal-Article
AB:  Stir bar sorptive extraction is a sampling technique for extraction of organic analytes from aqueous samples, which is based on sorption of analyte (or analytes) onto a thick film of polydimethylsiloxane (PDMS) coated on an iron stir bar.  The stir bar is inserted into the aqueous sample and extraction takes place during stirring.  A new sampling technique, headspace sorptive extraction (HSSE), was applied for the first time to headspace sampling of medicinal and aromatic plants.  Analyte partition coeff. between HSSE-PDMS stir bar and sample headspace (K1), the concentration factor (CF), reproducibility and min. recoverable amount were determined by analysing standard solutions of high volatility C5-C7 compounds with different polarities and structures (cyclohexane, propyl acetate, hexanal, 1-hexen-3-ol, isoamyl acetate, and 2-heptanol).  4 aromatic and medicinal plants, rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.), thyme (Thymus vulgaris L.) and valerian (Valeriana officinalis L.), were analysed by HSSE-GC with PDMS stir bars, and their concentration capacity was compared with those of static headspace and headspace solid phase microextraction with different fibres.  HSSE showed very high concentration capability with both standard and real sample components.

Record 155 of 187 in FSTA Current 1990-2001/09

AN:  2001-01-P0001
TI:  Shelf-life prediction of processed milk by solid-phase microextraction, mass spectrometry, and multivariate analysis.
AU:  Marsili-RT
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (8) 3470-3475, 12 ref.
DT:  Journal-Article
AB:  A technique based on solid-phase microextraction, MS, and multivariate analysis (SPME-MS-MVA) was used to predict the shelf life of pasteurized and homogenized reduced-fat milk and whole-fat chocolate milk sampled over a 7-month period.  Using SPME-MS-MVA, which is essentially an MS-based electronic-noise instrument, volatile bacterial metabolites were extracted from milk with SPME (Carboxen-PDMS) and injected into a GC capillary column at elevated temp. Mass fragmentation profiles from the unresolved milk volatile components were normalized to the intensity of a chlorobenzene internal standard mass peak (m/z 112) and subjected to MVA.  Prediction models based on partial least-squares regression of mass intensity lists were able to predict the shelf life of samples to approx. plus/minus1 day, with correlation coeff. greater than 0.98 for the 2 types of milk samples.  Using principal component analysis techniques, the procedure was also useful for classifying samples that were rendered unpalatable by nonmicrobial sources (contamination by copper and sanitizer) as well as by bacteria.

Record 156 of 187 in FSTA Current 1990-2001/09

AN:  2001-01-J0016
TI:  Formation of volatile branched chain esters in bananas (Musa sapientum L.)
AU:  Wyllie-SG; Fellman-JK
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (8) 3493-3496, 17 ref.
DT:  Journal-Article
AB:  Substrates controlling the formation of branched chain volatile esters in ripening bananas were investigated by the application of alcohol and amino acid precursors to whole fruit and tissue samples.  Resulting changes in the profile of the volatile esters following addition of alcohol or amino acid precursors were determined using solid phase microextraction (SPME) and GC.  These changes revealed the selectivity characteristics of the esterification enzyme acyl alcohol transferase (AAT), the availability of acyl CoA for ester formation, and the role of substrate supply on volatile production.  Results suggest that substrate supply is a major determinant of the quantitative and qualitative composition of the resulting banana aroma profile.

Record 157 of 187 in FSTA Current 1990-2001/09

AN:  2001-01-J0156
TI:  Sample preparation in the determination of phenolic compounds in fruits.
AU:  Antolovich-M; Prenzler-P; Robards-K; Ryan-D
PY:  2000
SO:  Analyst-; 125 (5) 989-1009, 237 ref.
DT:  Review
AB:  Methods for determining levels of phenols in fruits, fruit juices and related products are reviewed with emphasis on sample preparation methods.  Aspects covered include:  extraction methods available for sample preparation (including solid-phase microextraction, enzymic treatments); use of hydrolysis in extraction processes (as an aid to structural elucidation and characterization of glycosides, and for analysis of phenolic acids in citrus fruits and fruit juices); extraction of phenols from fruit extracts (juices and related products (fruit purees, red wines), olive oil, by-products of fruit processing); methods of phenol recovery from fruits (citrus fruits, berries, apples, olives); ways of extracting phenols from peel and seeds; isolation of phenols from leaves; techniques used for quantification of phenols (direct methods for total phenol content, chromatographic methods, atmospheric pressure ionization); and driving forces directing research into analytical techniques for fruit phenols analysis (production of natural food antioxidants and functional foods, detection of adulteration).  Conditions are presented for extraction and determination of phenols from 78 fruit products (including fruits, fruit juices, fruit purees, wines, etc.).

Record 158 of 187 in FSTA Current 1990-2001/09

AN:  2001-01-H0123
TI:  Determination of Se-4-+ in drinkable water by solid-phase microextraction and gas chromatography/mass spectrometry.
AU:  Guidotti-M
PY:  2000
SO:  Journal-of-AOAC-International; 83 (5) 1082-1085, 28 ref.
DT:  Journal-Article
AB:  A method was developed for the selective determination of Se-4-+ in drinking water by solid-phase microextraction (SPME) and GC/MS.  Se-4-+ was selectively derivatized to ethane, 1,1'-selenobis by reaction with sodium tetraethylborate, extracted by the SPME fibre method, and determined by GC/MS.  Both headspace (HS)-SPME and direct SPME were studied.  The method requires only a small sample vol. and 20 min for completion.  At 2.0 mug/l concn., the relative s.d. was 10.1% for HS-SPME and 9.1% for direct SPME.  For HS-SPME, the theoretical detection limit was 81 ng/l; theoretical detetion limit was 166 ng/l for direct SPME.  The recovery rate was 95%.  The method was used to determine Se-4-+ in 10 tap water samples.  Se-4-+ concn. in these samples were below the detection limit.

Record 159 of 187 in FSTA Current 1990-2001/09

AN:  2001-01-H0028
TI:  Measurement of trihalomethanes in potable and recreational waters using solid phase micro extraction with gas chromatography-mass spectrometry.
AU:  Stack-MA; Fitzgerald-G; O'Connell-S; James-KJ
PY:  2000
SO:  Chemosphere-; 41 (11) 1821-1826, 22 ref.
DT:  Journal-Article
AB:  Application of solid phase microextraction (SPME) to the analysis of 4 trihalomethanes (THM; chloroform, bromodichloromethane, dibromochloromethane and bromoform) in drinking water and swimming pool water is reported.  Headspace SPME was performed using a fused silica fibre with a 100 mum polydimethylsiloxane coating; extracted analytes were then subjected to thermal desorption at 220 degree C and analysed by GC-MS.  As the proposed EU regulatory limit for THM in drinking water is 100 mug/l, an analyte concn. linear working range of 10-160 mug/l was established; relative s.d. fell within the range 0.9-19%.  Limits of detection ranged from 1.0-2.8 mug/l.  Water samples from a number of different public water supply systems in the Republic of Ireland were analysed by the method; THM were detected in all samples.  The highest THM concn. determined in drinking water was 61.8 mug/l while the lowest concn. recorded was 16.1 mug/l; all samples were within the proposed EU directive limit.  It is concluded that the technique shows high sensitivity, specificity and reproducibility and can be used for rapid screening of water samples for THM.

Record 160 of 187 in FSTA Current 1990-2001/09

AN:  2000-12-J2580
TI:  Application of solid phase micro-extraction (SPME) to the analysis of pesticide residues in vegetables.
AU:  Volante-M; Pontello-M; Valoti-L; Cattaneo-M; Bianchi-M; Colzani-L
PY:  2000
SO:  Pest-Management-Science; 56 (7) 618-636, 23 ref.
DT:  Journal-Article
AB:  Solid phase microextraction (SPME) was applied to the analysis of a mixed vegetable matrix (containing homogenized potatoes and legumes) spiked with approx. 100 different pesticides.  SPME was conducted using 2 different adsorbent phase fibres (polydimethylsiloxane and Carbowax/divinylbenzene).  The vegetable matrix was also analysed using a conventional multi-residue method for comparative purposes.  Pesticides were added to the matrix at concn. of 0.01-1 mg/kg to evaluate the performance of SPME at varying analytical responses.  Results generally showed good agreement with those obtained by the conventional method; however some active compounds were poorly recovered or not detected by SPME.  Analysis of real samples and certified reference matrices (celery and grape purees) by SPME resulted in poor recoveries of some pesticides; pre-extraction of samples with acetone followed by sonication prior to SPME analysis improved method performance.

Record 161 of 187 in FSTA Current 1990-2001/09

AN:  2000-12-H2710
TI:  Speciation of trimethyllead and triethyllead by in-tube solid phase microextraction high-performance liquid chromatography electrospray ionization mass spectrometry.
AU:  Mester-Z; Lord-H; Pawliszyn-J
PY:  2000
SO:  Journal-of-Analytical-Atomic-Spectrometry; 15 (6) 595-600, 30 ref.
DT:  Journal-Article
AB:  An analytical method was developed for determination of trimethyllead (TML) and triethyllead (TEL) species in aqueous samples.  In tube-solid phase microextraction (SPME) and HPLC are coupled to a quadrupole MS using electrospray (ES) as an ionization interface.  Optimization of instrumental parameters is described, including evaluation of 3 commercial GC capillaries for in-tube SPME experiments.  Elemental (-2-0-8Pb-+) and molecular forms TML and TEL (mlz 253 and 295, respectively) were monitored simultaneously to provide complete speciation information.  Results from in-tube SPME-HPLC-ESMS experiments indicated that complete separation and detection TML and TEL can be achieved in less than 5 min.  Precision was greater than 5% and estimated limits of detection were 11.3 and 12.6 ng ml---1, respectively, for TML and TEL at a solution flow rate of  450 mul min---1.  Recoveries of TML and TEL added to tap water at 50-200 ng ml---1 were 103-126%.  No organolead was detected in unspiked drinking water.

Record 162 of 187 in FSTA Current 1990-2001/09

AN:  2000-12-H2810
TI:  Relationships between the volatile compounds evaluated by solid phase microextraction and the thermal treatment of tomato juice:  optimization of the blanching parameters.
AU:  Servili-M; Selvaggini-R; Taticchi-A; Begliomini-AL; Montedoro-G
PY:  2000
SO:  Food-Chemistry; 71 (3, Cost action 96:  food and flavour) 407-415, 31 ref.
DT:  Journal-Article
AB:  Blanching of tomato juice was optimized by applying reponse surface methodology (RSM) to the composition of volatile compounds extracted by solid phase microextraction (SPME) from tomato juice.  190 volatile compounds were sampled by SPME; 102 of them were identified, and the others identified tentatively, using GC-MS.  Identities of all the headspace volatiles are presented.  Blanching modified mainly contents of saturated and unsaturated C6 alcohols and aldehydes, esters, ketones and carotenoid derivatives.  Optimal conditions for blanching were determined, by RSM, to be 67 degree C for 24 min (cold break treatment) and 86 degree C for 3.5 min (hot break treatment).

Record 163 of 187 in FSTA Current 1990-2001/09

AN:  2000-12-H2603
TI:  On the enantiomeric distribution of R(-) and S(+) linalool in `muscat wine'.
AU:  Tateo-F; Bononi-M; Lubian-E
PY:  2000
SO:  Rivista-di-Viticoltura-e-di-Enologia; 53 (1) 21-26, 12 ref.
DT:  Journal-Article
AB:  Linalool is one of the main characteristic flavour compounds in muscat wines.  Investigations were conducted on 12 samples of Moscatel Favaios (a Portuguese wine made by a process similar to port manufacture) to assess enantiomeric distribution of linalool.  3 different methods for extraction of linalool (solid phase microextraction (SPME), steam distillation and solvent extraction) were used; their effects on linalool enantiomer distribution were evaluated by GC chiral analysis.  Results are presented as enantiomeric excess (ee%) of the S(+) form.  Ranges of values for ee% of the S(+) form were:  SPME, 13.0-16.2; solvent extraction, 16.0-18.8; and steam distillation, 5.0-9.6.  Coeff. of variation were similar for all 3 extraction methods.  It is suggested that steam distillation results in partial racemization of linalool as a result of high temp.  The other 2 extraction methods agreed well, and are suitable for this application.

Record 164 of 187 in FSTA Current 1990-2001/09

AN:  2000-12-C1501
TI:  Headspace solid-phase microextraction-capillary gas chromatography-ICP mass spectrometry for the determination of the organotin pesticide fentin in environmental samples.
AU:  Vercauteren-J; Meester-A-de; Smaele-T-de; Vanhaecke-F; Moens-L; Dams-R; Sandra-P
PY:  2000
SO:  Journal-of-Analytical-Atomic-Spectrometry; 15 (6) 651-656, 34 ref.
DT:  Journal-Article
AB:  Extraction and preconcentration capabilities of headspace solid-phase microextraction (SPME) were combined with the separation power of capillary GC and the low limits of detection (LOD) of inductively coupled plasma MS (ICP-MS) for detemination of the organotin compound triphenyltin (TPhT or fentin) in aqueous standard solutions, and in potatoes and mussels after digestion with tetramethylammonium hydroxide (TMAH) or KOH-EtOH.  Throughout, tricylcohexyltin (cyhexatin, TCT) was used as an internal standard.  Derivatization to transform TPhT and TCT into sufficiently volatile compounds was carried out with sodium tetraethylborate (NaBEt4), at pH 8 (0.2 mol l---1 ammonium buffer).  Headspace extraction was performed for 10-20 min at 75 or 85 degree C (depending on the type of sample) with a 100 mum polydimethylsiloxane (PDMS) fibre.  Absorption curves showed that even at high temp. (75 degree C) no equilibrium conditions were obtained for either compound.  Direct aqueous SPME was also studied, but the sensitivity was 11x lower at 25 degree C than that observed when using headspace SPME at 75 degree C.  After 2 min desorption of the SPME fibre at 270 degree C in the GC inlet, organotin compounds were separated on a capillary column with a polydimethysiloxane coating and transported into the ICP by means of a home-made heated (270 degree C) transfer line.  Monitoring of the -1-2-0Sn-+ signal by ICP-MS during GC provided extremely low LOD for fentin in water (2 pg l---1 (instrumental) and 125 pg l---1 (procedure)) as well as a good repeatability of 8% relative s.d. (n = 10).  Concn. of 3-10 and 0.9-3 ng g---1 (dry wt. as Sn), were found in mussels and potatoes, respectively.

Record 165 of 187 in FSTA Current 1990-2001/09

AN:  2000-11-T1019
TI:  Use of the MS-sensor to discriminate between different dosages of garlic flavoring in tomato sauce.
AU:  Dittmann-B; Zimmermann-B; Engelen-C; Jany-G; Nitz-S
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (7) 2887-2892, 31 ref.
DT:  Journal-Article
AB:  A method was developed to discriminate between different dosages of garlic flavouring in tomato sauce using a MS based sensory system.  4 fragment ions m/z 73, 81, 114 and 120 were selected as `sensor array' during direct injection of the sample headspace into the mass spectrometer.  Tomato sauces blended with different types of flavouring could be discriminated, and concn. gradients could be monitored.  Fragment ions were chosen after volatile components had been analysed and identified by SPME-GC/MS and HS-GC/MS (fullscan).  HS-GC/MS profiles of m/z 73, 81, 114 and 120 were recorded in the selected ion monitoring mode.  It is suggested that this MS-sensor may be suitable as a quality control device for seasoning dosage regulation during the manufacture of tomato sauces.

Record 166 of 187 in FSTA Current 1990-2001/09

AN:  2000-11-S1631
TI:  APC values and volatile compounds formed in commercially processed, raw chicken parts during storage at 4 and 13 degree C and under simulated temperature abuse conditions.
AU:  Senter-SD; Arnold-JW; Chew-V
PY:  2000
SO:  Journal-of-the-Science-of-Food-and-Agriculture; 80 (10) 1559-1564, 14 ref.
DT:  Journal-Article
AB:  The relationship between generation of volatile compounds (VC) and increases in aerobic plate count (APC) was examined at 24 h intervals in commercially processed chicken parts (skinless breast fillets, thighs, wings and boneless breasts with skin), which had been bagged and stored at 4 and 13 degree C for less than or equal5 days.  Headspace VC were analysed by GC, GC-MS and GC with chemiluminescence detection following solid phase microextraction and direct headspace sampling.  APC were enumerated on APC agar.  Results showed that VC produced during storage under refrigerated conditions (4 degree C) did not indicate diminishing meat quality, because the duration of time under which meat was stored at this temp. did not allow for bacterial spoilage.  However, under temp. abuse conditions (13 degree C), VC analysis was shown to be a more useful tool in determining meat quality as bacterial numbers reached spoilage levels.  Only 7 (ethanol, acetone, methyl ethyl ketone, ethyl acetate, hydrogen sulphide, dimethyl sulphide and carbon disulphide) out of 17 VC identified occurred consistently, and were therefore deemed more representative of VC production during storage of the samples.

Record 167 of 187 in FSTA Current 1990-2001/09

AN:  2000-11-R0801
TI:  Using microwave distillation-solid-phase microextraction-gas chromatography-mass spectrometry for analyzing fish tissue.
AU:  Grimm-CC; Lloyd-SW; Batista-R; Zimba-PV
PY:  2000
SO:  Journal-of-Chromatographic-Science; 38 (7) 289-296, 15 ref.
DT:  Journal-Article
AB:  A technique for analysis of volatile compounds from fish tissue employing microwave distillation-solid-phase microextraction-GC MS is described.  A qualitative listing of 174 compounds observed in the headspace for cooked catfish is given, and a quantitative method for determination of off-flavour contaminants (2-methylisoborneol and geosmin) is presented.  Borneol and decahydro-1-naphthol are used as the surogate and internal standards, respectively.  A linear calibration curve was obtained for 0.1-5 p.p.b. with a recovery of 60% at 2.5 p.p.b.  Comparison of the instrumental method with a human flavour checker showed good agreement.

Record 168 of 187 in FSTA Current 1990-2001/09

AN:  2000-11-J2209
TI:  Determination of major aroma impact compounds in fermented cucumbers by solid-phase microextraction-gas chromatography-mass spectrometry-olfactometry detection.
AU:  Marsili-RT; Miller-N
PY:  2000
SO:  Journal-of-Chromatographic-Science; 38 (7) 307-314, 11 ref.
DT:  Journal-Article
AB:  Purge-and-trap, solid-phase extraction, and solid-phase microextraction-GC MS (SPME-GC-MS) sample preparation techniques for analysis of odour impact chemicals in fermented cucumber brine were compared.  SPME-GC-MS was coupled with detection frequency olfactometry experiments to determine key impact odour compounds in the brine.  Results indicated that the most potent odorants that define the typical characteristic brine aroma are trans-4-hexenoic acid and cis-4-hexenoic acid.  The identity of key impact odorants in brine was confirmed by recombination experiments.

Record 169 of 187 in FSTA Current 1990-2001/09

AN:  2000-11-H2369
TI:  Solid-phase microextraction method for the quantitative analysis of styrene in water.
AU:  Silva-FC; Carvalho-CR-de; Cardeal-Z-de-L
PY:  2000
SO:  Journal-of-Chromatographic-Science; 38 (7) 315-318, 14 ref.
DT:  Journal-Article
AB:  A headspace solid-phase microextraction (HS-SPME) method was developed for determination of styrene in drinking water.  GC MS is utilized for qualitative analysis.  A manual SPME holder with 85-mum polyacrylate coating is used to extract styrene from water.  The method showed good linearity (correlation coeff. r = 0.9999 for 1.00-100.00 mug/l), a relative s.d. of 1.9%, and a detection limit of 0.30 mug/l.  This method compared favourably with a classical headspace GC method.  The method was used to study styrene contents of river water and drinking water stored in plastics cups.  Even at pH values typical of those found in soft drinks, no styrene migrated from the cups into the water, except for water at 80 degree C which contained increasing amounts of styrene as storage time increased from 5 to 30 min.

Record 170 of 187 in FSTA Current 1990-2001/09

AN:  2000-10-T0902
TI:  Formation of volatile compounds during heating of spice paprika (Capsicum annuum) powder.
AU:  Cremer-DR; Eichner-K
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (6) 2454-2460, 45 ref.
DT:  Journal-Article
AB:  Spice paprika (red pepper; Capsicum annuum), the most cultivated spice worldwide, is used mainly for its colour and pungency.  However, current research is also focusing on paprika flavour.  In this study, kinetics of formation of volatiles that indicate a decrease in paprika quality due to Maillard reaction, hydrolytic reactions and oxidative degradation reactions of lipids, such as fatty acids and carotenoids, were investigated.  Paprika volatiles were analysed quantitatively using headspace GC and solid-phase microextraction followed by GC-MS.  Kinetics of their formation were investigated, and their respective activation energies determined.  Strecker aldehyde, acetone and methanol formation followed pseudo-zero-order reaction kinetics, and formation of dimethyl sulphide (DMS) was characterized by a first-order kinetic.  Activation energies determined were between 86.3 and 101.8 for the Strecker aldehydes, acetaldehyde, 2-methylpropanal, 3-methylbutanal and 2-methylbutanal, 130.7 for acetone, 114.2 for methanol, and 109.7 kJ/mol for DMS.  Amounts of Strecker aldehydes formed were correlated to the concn. of the corresponding free amino acids present in the samples.  Formation of hexanal and 6-methyl-5-hepten-2-one in C. annuum during processing was confirmed and formation of beta-ionone was described, probably for the first time.  During heating, hexanal concn. increased rapidly.  Formation of 6-methyl-5-hepten-2-one suggests that C. annum fruits contain lycopene.

Record 171 of 187 in FSTA Current 1990-2001/09

AN:  2000-10-T0900
TI:  Volatile compounds produced from monosodium glutamate in common food cooking.
AU:  Chung-May-Wu; Ziyang-Wang; Qiao-Hong-Wu
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (6) 2438-2442, 28 ref.
DT:  Journal-Article
AB:  Identities of volatile compounds produced by monosodium glutamate (MSG) during cooking were investigated.  A mixture of soybean oil and/or water, sugar and/or MSG was water-boiled or oil-heated at 100, 120, 140, 160 or 170 degree C, respectively, and volatile compounds produced were isolated by solid-phase microextraction and identified by GC and GC-MS.  Oxidative thermal degradation products of fatty acids (OTDPFA) were the major volatile compounds detected for all water-boiled samples.  When MSG and sugar were heated together, 2,5-dimethyl pyrazine and methyl pyrazine were also detected at or after 160 min heating.  Water added in soybean oil increased OTDPFA production.  In oil-heated samples of soybean oil alone, soybean oil with MSG, and soybean oil with sugar, OTDPFA were also the major compounds found.  Samples containing MSG also produced 2-pyrrolidone, and the samples containing sugar also produced furfural and 5-hydroxy methyl furfural  Samples containing soybean oil, sugar, and MSG produced 23 pyrazines, OTDPFA, and gamma-butyrolactone as the major volatile compounds.  Contents of OTDPFA were lower in MSG plus sugar and MSG-added samples, and it is postulated that antioxidant activities were produced during cooking.

Record 172 of 187 in FSTA Current 1990-2001/09

AN:  2000-10-S1440
TI:  Solid phase microextraction/gas chromatography of Salmonella-infected beef.
AU:  Ogihara-H; Horimoto-Y; Zhi-Hai-Wang; Skura-BJ; Nakai-S
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (6) 2253-2259, 7 ref.
DT:  Journal-Article
AB:  Feasibility of solid phase microextraction (SPME) and GC analysis of the volatile compounds produced by pathogenic bacteria as a method for their detection in foods was investigated.  Initially, 8 strains of Salmonella were incubated in tripticase soy broth at 37 degree C for 24 h; the volatile compounds produced were collected by SPME and analysed by GC.  Analysis of the similarity of the GC patterns produced for each strain, using principal component similarity scattergrams, showed that the strains could be separated.  This method was also able to distinguish 5 food-contaminating bacteria (S. enteritidis, S. typhimurium, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli) and 10 other bacteria (including a strain of Salmonella), grown in the same medium.  Analysis of samples of ground beef inoculated with Salmonella enteritidis and other bacteria showed that the method was most effective when the samples were placed in a suitable culture medium and subjected to a secondary incubation

Record 173 of 187 in FSTA Current 1990-2001/09

AN:  2000-10-R0748
TI:  Determination of methylmercury by solid-phase microextraction inductively coupled plasma mass spectrometry:  a new sample introduction method for volatile metal species.
AU:  Mester-Z; Lam-J; Sturgeon-R; Pawliszyn-J
PY:  2000
SO:  Journal-of-Analytical-Atomic-Spectrometry; 15 (7) 837-842, 38 ref.
DT:  Journal-Article
AB:  Direct coupling of solid-phase microextraction (SPME) with inductively coupled plasma mass spectrometry (ICP-MS) is described for methylmercury speciation.  A thermal desorption interface, consisting of a heated, glass-lined splitless-type GC injector, was placed directly at the base of the torch to minimize the length of transfer line.  This arrangement provided for fast desorption and high sample introduction efficiency.  Direct liquid immersion and headspace extraction of methylmercury were studied, including the effects of temp. and time on extraction efficiency.  For clean solutions, immersion sampling SPME provided good sensitivity that was linear over 2 orders of magnitude, whereas headspace sampling showed 15% lower sensitivity, but a linear range of greater than 3 orders of magnitude.  Detection limit for headspace methylmercury sampling was 0.2 ng ml ---1.  Calibration by the method of additions using direct extraction revealed a severe matrix effect with biological tissue samples, diminishing the methylmercury response 70-fold, whereas that obtained by headspace extraction was statistically indistinguishable from signals generated using matrix free standards.  Analytical results showed good agreement between certified and measured values for analysis of NRCC DORM-2 (Dogfish muscle) and DOLT-2 (Dogfish liver) reference materials.

Record 174 of 187 in FSTA Current 1990-2001/09

AN:  2000-10-N0556
TI:  Headspace solid-phase microextraction use for the characterization of volatile compounds in vegetable oils of different sensory quality.
AU:  Jelen-HH; Obuchowska-M; Zawirska-Wojtasiak-R; Wasowicz-E
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (6) 2360-2367, 20 ref.
DT:  Journal-Article
AB:  Headspace solid-phase microextraction (HS-SPME) was used to isolate volatile compounds formed during peroxidation of fatty acids in vegetable oils.  Isolated compounds were characterized by GC-MS and quantified using GC with FID detection.  A divinylbenzene/carboxene/PDMS fibre gave the best detection of analysed compounds.  Extraction curves, limits of detection, repeatability and linearity were investigated for the products of fatty acid autoxidation, including 14 aldehydes, ketones, hydrocarbons and alcohols.  Limits of detection for 11 of these were less than 1 mug/l.  For quantitative purposes, to minimize the influence of temp. on hydroperoxide formation and the changes in  the volatiles profile of the extracts, sampling was performed at 20 degree C.  For compound characterization by GC-MS, a sampling temp. of 50 degree C was applied.  The method was applied to the analysis of refined and cold-pressed rapeseed oils stored at 60 degree C for 10 days, and for 10 different vegetable oils with various degrees of peroxidation.  All samples were subjected to sensory analysis, and principal component analysis of results was related to the amount of volatile compounds isolated by SPME.  Where the amount of compounds was high, samples were perceived as least desirable according to sensory analysis, whereas those with low levels of volatile compounds were most desirable.  This relationship was observed for both total volatiles, quantified C5-C9 aldehydes and 14 compounds selected during method development.  It is suggested that SPME is a rapid and sensitive method for the extraction and quantitation of trace volatile compounds from plant oils even at ambient temp.

Record 175 of 187 in FSTA Current 1990-2001/09

AN:  2000-10-H2230
TI:  Solid-phase microextraction method development for headspace analysis of volatile flavor compounds.
AU:  Roberts-DD; Pollien-P; Milo-C
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (6) 2430-2437, 24 ref.
DT:  Journal-Article
AB:  Solid-phase microextraction (SPME) fibres were evaluated for their ability to adsorb volatile flavour compounds from coffee and a model flavoured aqueous solution, under various conditions.  Experiments comparing different fibres showed that poly(dimethylsiloxane)/divinylbenzene had the highest overall sensitivity.  Carboxen/poly(dimethylsiloxane) was the most sensitive to small molecules and acids.  As the concn. of compounds increased, the quantitative linear range was exceeded as shown by competition effects with 2-isobutyl-3-methoxypyrazine at concn. greater than 1 p.p.m.  A method based on a short-time sampling of the headspace (1 min) was shown to better represent the equilibrium headspace concn.  Analysis of coffee brew with a 1-min headspace adsorption time was verified to be within the linear range for most compounds and thus appropriate for relative headspace quantification.  Absolute quantification of volatiles, using isotope dilution assays (IDA), was not subject to biases caused by excess compound concn. or complex matrices.  Degradation of coffee aroma volatiles during storage was followed by relative headspace measurements and absolute quantification.  Both methods gave similar values for 3-methylbutanal, 4-ethylguaiacol, and 2,3-pentanedione.  Acetic acid, however, gave higher values during storage upon relative headspace measurements due to concurrent pH decreases that were not seen with IDA.

Record 176 of 187 in FSTA Current 1990-2001/09

AN:  2000-10-B1578
TI:  Evaluation of solid-phase microextraction for the isotopic analysis of volatile compounds produced during fermentation by lactic acid bacteria.
AU:  Goupry-S; Rochut-N; Robins-RJ; Gentil-E
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (6) 2222-2227, 14 ref.
DT:  Journal-Article
AB:  In an attempt to develop an improved method for analysis of the flavour compounds produced during fermentation of foods by lactic acid bacteria, solid-phase microextraction (SPME) coupled with isotope ratio MS (IRMS) was used to evaluate the flavour compounds produced by the lactic acid bacterium Lactococcus lactis ssp. lactis biovar. diacetylactis using both liquid and headspace sampling modes.  Initially, it was necessary to optimize the conditions for SPME extraction of the flavour compounds diacetyl and acetoin in standard aqueous solutions.  Effects of salt, headspace vs. liquid sampling, and coating phase were tested.  The suitability of coupling SPME and GC-combustion interface IRMS (GC C IRMS) for determination of delta-1-3C values of the flavour compounds was also assessed.  It was shown that neither the analyte concn. nor the period of fibre exposure has an effect on the delta-1-3C values.  Results suggest that, having verified the absence of matrix effects from the fermentation medium, flavour compounds can be extracted directly from culture supernatant by SPME and their delta-1-3C values can be obbained by GC-C-IRMS.

Record 177 of 187 in FSTA Current 1990-2001/09

AN:  2000-09-J1801
TI:  Volatile changes during dehydration of d'Agen prunes.
AU:  Sabarez-HT; Price-WE; Korth-J
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (5) 1838-1842, 30 ref.
DT:  Journal-Article
AB:  Solid phase microextraction (SPME) was used in conjunction with GC-MS to monitor the change in some major volatile flavours during drying of d'Agen plums.  Plums were dried under simulated commercial drying conditions (80 degree C air temp., 35% RH, 5 m/s air velocity).  The aroma profile was significantly modified during drying and substantial loss of the original volatile flavours was observed.  The generation of some compounds was shown to be due to the thermal decomposition of carbohydrates.  The importance of aroma profiling in detecting the progress of the chemical (degradation) reactions during plum drying, and identification of marker volatiles for quality control of the product are discussed.

Record 178 of 187 in FSTA Current 1990-2001/09

AN:  2000-09-H2047
TI:  Comparison of flavor compounds in steamed- and nonsteamed-roasted Polygonatum odoratum roots by solid-phase microextraction.
AU:  Nan-Young-Park; Ji-Hyung-Seo; Young-Hoi-Kim; Joong-Ho-Kwon
PY:  2000
SO:  Korean-Journal-of-Food-Science-and-Technology; 32 (3) 507-512, 26 ref.
DT:  Journal-Article
AB:  Tea prepared from roasted Polygonatum odoratum roots, both steamed and nonsteamed, was evaluated for flavour profiles, using solid-phase microextraction on Carbowax/divinylbenzene (60 degree C for 30 min) and GC-MS.  Volatile compounds in tea samples roasted for 15 min at 130 degree C were similar regardless of steaming, although some differences were observed in peak characteristics.  Of 45 peaks obtained, 25 could be identified.  Pyrazine levels were relatively high, particularly in nonsteamed samples, whereas steamed samples showed higher levels of acetic acid and hexanoic acid.

Record 179 of 187 in FSTA Current 1990-2001/09

AN:  2000-08-T0718
TI:  Monoterpene biosynthesis in Mentha x piperita L.:  bioconversion of piperitone and piperitenone.
AU:  Fuchs-S; Gross-A; Beck-T; Mosandl-A
PY:  2000
SO:  Flavour-and-Fragrance-Journal; 15 (2) 84-90, 15 ref.
DT:  Journal-Article
AB:  To investigate the stereoselectivity of the bioconversion of piperitone and piperitenone in peppermint, deuterium-labelled precursors were synthesized and fed to Mentha x piperita L. shoot tip and first leaf pair.  After feeding for 24-29 h, the plant material was removed from the solutions and essential oils were prepared by solid phase microextraction.  Enantioselective multidimensional GC MS was used to analyse the essential oils for monoterpenes.  Both labelled racemic piperitone and achiral piperitenone were converted into 1R-configured (-)-menthone and (+)-isomenthone, and preferably to the (+)-isomenthone.  Possible pathways for the bioconversions are discussed.

Record 180 of 187 in FSTA Current 1990-2001/09

AN:  2000-08-H1843
TI:  Are musk compounds useful indicators for polluted drinking water?
AU:  Noser-J; Sutter-A; Auckenthaler-A
PY:  2000
SO:  Mitteilungen-aus-Lebensmitteluntersuchung-und-Hygiene; 91 (1) 102-115, 14 ref.
DT:  Journal-Article
AB:  Polycyclic musk and nitromusk compounds are manufactured on an extensive industrial scale for use in perfumes and cosmetic products, and have been detected in a range of environmental samples.  This study examined the feasibility of using musk compounds as indicators of industrial pollution of drinking water by determining their ease of detection and their occurrence in various water sources.  Analyses were carried out by solid phase microextraction (SPME) coupled to GC-MS in sewage treatment outlets and for various water (including river and drinking water) samples from the Swiss canton of Basel-Landschaft.  Nitromusk compounds were only detected in sewage treatment outlets, and at low concn. (100 ng/l); they were therefore regarded as unsuitable as indicator compounds.  Polycyclic musk compounds however, were found in sewage treatment outlets and in surface water at concn. between 20 ng and 6 mug/l; they were not detected in groundwater or drinking water.  Studies at a treatment plant showed that coarse filtration of river water decreased the concn. of polycyclic musk compounds by between 20 and 60%.  It is concluded that analysis of polycyclic musk compounds may be a suitable means of identifying anthropogenic pollution of drinking water.

Record 181 of 187 in FSTA Current 1990-2001/09

AN:  2000-08-H1729
TI:  Analysis of benzothiazole in Italian wines using headspace solid-phase microextraction and gas chromatography-mass spectrometry.
AU:  Bellavia-V; Natangelo-M; Fanelli-R; Rotilio-D
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (4) 1239-1242, 20 ref.
DT:  Journal-Article
AB:  Benzothiazoles (BTH) are a part of the molecular structure of a large number of natural products, biocides, drugs, industrial chemicals and food flavours and aromas.  They are found in the environment mainly as a result of their use in rubber vulcanization.  In this study, a new headspace solid-phase microextraction (HS-SPME) method for analysis of BTH in wine is described.  This method is fast, inexpensive, and does not require solvents.  The detection limit of BTH in wine was 45 p.p.t. with linearity up to 100 p.p.b.  Quantification of BTH was performed using the standard additions method, which does not require the use of an internal standard.  12 wines from different grape var. grown in several regions were analysed using SPME extraction and GC-MS detection.  Under these experimental conditions, BTH was found in all wines analysed.  Concn. levels in samples varied from 0.24 mug/l (Vermentino) to 1.09 mug/l (Franciacorta).  The origin of the BTH in the wines was unclear.

Record 182 of 187 in FSTA Current 1990-2001/09

AN:  2000-07-T0609
TI:  Examination of the enantiomeric distribution of certain monoterpene hydrocarbons in selected essential oils by automated solid-phase microextraction-chiral gas chromatography-mass selective detection.
AU:  Coleman-WM III; Lawrence-BM
PY:  2000
SO:  Journal-of-Chromatographic-Science; 38 (3) 95-99, 20 ref.
DT:  Journal-Article
AB:  A viable approach to determination of the sources of essential oils, based on analysis of the enantiomeric distribution of chiral compounds by automatic injection solid-phase microextraction-chiral-GC-mass selective detection, is demonstrated.  With no sample preparation, the source of essential oils such as peppermint, spearmint and rosemary could be distinguished easily.  Short fibre exposure times of approx. 6 s to the headspace above submicrolitre quantities of the selected oils were all that was required to obtain both the required sensitivity and resolution to afford analyses with excellent reproducibilities (relative s.d. values consistently less than 5.0%).  Enantiomeric distribution patterns characteristic of botanic source and variations due to geographical origin and adulteration were revealed.

Record 183 of 187 in FSTA Current 1990-2001/09

AN:  2000-07-J1381
TI:  Frozen storage effects on anthocyanins and volatile compounds of raspberry fruit.
AU:  Ancos-B-de; Ibanez-E; Reglero-G; Cano-MP
PY:  2000
SO:  Journal-of-Agricultural-and-Food-Chemistry; 48 (3) 873-879, 26 ref.
DT:  Journal-Article
AB:  Quantitative and qualitative evolution of anthocyanins and volatile compounds of 4 raspberry cv. (Heritage, Autumn Bliss, Zeva and Rubi) growing in Spain were analysed in raw or just frozen fruit, and during long-term frozen storage of fruit at -20 degree C for 1 yr.  Headspace solid-phase microextraction (HS-SPME) coupled with GC-MS and HPLC were employed to study evolution of volatile compounds and individual anthocyanins, respectively.  Volatile aroma composition changes produced by freezing and long-term frozen storage were minimal.  A significant increase in extraction capacity was obtained only for alpha-ionone (27%) and for caryophyllene (67%) in Heritage at 12 months of storage.  Stability of anthocyanins to freezing and frozen storage depended on the seasonal period of harvest.  Heritage and Autumn Bliss (early cv.) were less affected by processing and long-term frozen storage (1 yr); total pigment extracted showed a tendency to increase by 17 and 5%, respectively.  Rubi and Zeva (late cv.) showed a decreasing trend in total anthocyanin content of 4% for Rubi and 17.5% for Zeva. Cyanidin 3-glucoside most easily suffered the degradative reactions that take place during processing and storage.

Record 184 of 187 in FSTA Current 1990-2001/09

AN:  2000-07-H1634
TI:  Analysis of brandy aroma by solid-phase microextraction and liquid-liquid extraction.
AU:  Ebeler-SE; Terrien-MB; Butzke-CE
PY:  2000
SO:  Journal-of-the-Science-of-Food-and-Agriculture; 80 (5) 625-630, 27 ref.
DT:  Journal-Article
AB:  Solid-phase microextraction (SPME) was used to analyse volatile compounds from alambic pot-still brandy; 3 stationary-phase fibre coatings were initially considered, but a polydimethylsiloxane fibre was used, because divinylbenzene and polyacrylate showed significant affinity for ethanol.  Results were compared with those of conventional liquid-liquid extraction (LLX) using Freon.  Selectivity of SPME and LLX for specific classes of flavour compounds was evaluated, and SPME was combined with GC-olfactometry in an assessment of effects of grape cv. (Colombard vs. Ugni blanc) and maturity on brandy flavour.  SPME proved to be a rapid, but selective, extraction method, but to provide a complete quantitative analysis of volatiles, greater than or equal2 sample preparation techniques should be used.  Generally, SPME was more selective than LLX for esters and acids, whereas LLX could extract higher alcohols more efficiently.  Optimization of SPME fibre coating for analysis of volatiles in distilled alcoholic beverages would improve analyses.  The combination of SPME, LLX and GC-olfactometry provided detailed data on varietal origin and sensory properties of brandy.  Colombard brandy showed significantly higher levels of hexanol and 3-methylbutyl acetate, and significantly lower levels of 3-methylbutanol and 3-methylbutyl octanoate, than Ugni blanc brandy.

Record 185 of 187 in FSTA Current 1990-2001/09

AN:  2000-04-P0666
TI:  Application of solid phase micro extraction for the rapid analysis of chlorinated organics in breast milk.
AU:  Roehrig-L; Meisch-HU
PY:  2000
SO:  Fresenius'-Journal-of-Analytical-Chemistry; 366 (1) 106-111, 20 ref.
DT:  Journal-Article
AB:  A method for monitoring persistent organochlorine compounds in human milk using solid phase microextraction (SPME) and GC-ECD is described.  Hexachlorobenzene (HCB), alpha-, beta- and gamma-hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT) and its derivatives, and some important PCB congeners can be detected.  More polar substances, such as tri-, tetra- and penta-chlorophenols, can be analysed simultaneously with these less polar compounds without the need of derivatization for determination of phenolic compounds.  Reproducibility of results was good down to the lower mug/l-region.  The method was fast and of low cost compared with classic extraction and determination procedures.

Record 186 of 187 in FSTA Current 1990-2001/09

AN:  2000-04-B0639
TI:  Production of tomato flavor volatiles from a crude enzyme preparation using a hollow-fiber reactor.
AU:  Cass-BJ; Schade-F; Robinson-CW; Thompson-JE; Legge-RL
PY:  2000
SO:  Biotechnology-and-Bioengineering; 67 (3) 372-377, 19 ref.
DT:  Journal-Article
AB:  A crude microsomal fraction from ripe tomato fruit was used for production of hexanal, a commercially important flavour compound, from linoleic acid in a hollow-fibre bioreactor.  The reactor consisted of a XAMPLER ultrafiltration module coupled to a reservoir.  The enzyme template was extracted from ripe tomato fruit and processed by ultrafiltration (100 kDa cut-off) after which, the extract, enriched in soluble and membrane-associated lipoxygenase and hydroperoxide lyase, was recirculated through the lumen of the hollow-fibre ultrafiltration module together with linoleic acid.  Hexanal was extracted from the permeate by solid phase microextraction.  Using this system, hexanal production rate was 5.1 mug/min at an initial substrate concn. and transmembrane pressure of 16mM and 70 kPa, respectively.  The system was run continuously for 1 wk with no loss of activity during this time.  It is concluded that it is feasible to produce volatile flavour compounds using a crude extract of membrane-associated enzymes and a hollow fibre reactor.  The hollow fibre system allows retention of enzyme and substrate, and concomitant removal of product.

Record 187 of 187 in FSTA Current 1990-2001/09

AN:  2000-03-S0412
TI:  A comparison of solid-phase microextraction (SPME) fibres for measurement of hexanal and pentanal in cooked turkey.
AU:  Brunton-NP; Cronin-DA; Monahan-FJ; Durcan-R
PY:  2000
SO:  Food-Chemistry; 68 (3) 339-345, 24 ref.
DT:  Journal-Article
AB:  Recent introduction of several novel solid-phase microextraction (SPME) fibres with a potentially greater range of selectivities than was previously the case prompted this evaluation of their performance for quantitation of hexanal in the headspace of cooked turkey.  Fibres evaluated included 65 mum polydimethylsiloxane/divinylbenzene (PDMS/DVB) for polar volatiles and 65 mum Carbowax/DVB for extraction of polar analytes such as alcohols and for measurement of volatile compound profiles.  These fibres are mixed coating porous polymer solids which function by adsorption rather than absorption (as PDMS).  The other fibre evaluated was Carboxen/PDMS at 75 mum (coated with Carboxen 1006 adsorbent, particularly useful in trapping low mol. wt. volatile compounds such as solvents).  SPME-GC was satisfactory for hexanal and pentanal quantitation in cooked and stored turkey homogenate (16.6% homogenates containing 10mM BHA) headspace volatiles, with the PDMS/DVB fibre demonstrating the optimal combination of properties (reproducibility, sensitivity, linearity); quality of analysis was enhanced by use of 2-methyl pentanal as internal standard.  A good correlation with TBARS assessments of lipid oxidative stability was achieved.  During storage for 6 days, both TBARS and headspace pentanal by SPME-GC of turkey homogenates showed an initial increase to 4 days and then a slowing of the rate of increase, final values reaching approx. 0.22 mug pentanal/g muscle homogenate and a TBARS value of approx. 7.4 mg/kg muscle.
 
 

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