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Pyrolysis–mass spectrometry (Py–MS) is an analytical fingerprinting technique, that offers distinct advantages in the field of food analysis. The sample is quickly decomposed at several hundred degrees Celsius and the resulting fragments are analysed by mass spectrometry. The mass spectra are subsequently submitted to multivariate data analysis. Py–MS was successfully applied to the determination of the geographical origin of cocoa butters, the detection of added whey proteins in milk, the characterisation of vinegar and wine and the ripening stages of cheese. By a careful control of the pyrolysis, Py–MS can be applied for the determination of the 18O/16O ratio in food (pyrolysis–isotope ratio mass spectrometry, Py–IRMS). An example is given for the determination of the geographical origin of olive oils.

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Pyrolysis‐mass spectrometry (Py‐MS) is an analytical fingerprinting technique that, coupled with suitable multivariate data analysis procedures, offers a rapid method for the characterization of cocoa butters. Our results indicate this technique is capable of discriminating cocoa butters according to different geographical areas (America, Africa, Asia), independent of the different technological treatment (deodorization, alkalization) during production or the presence of other vegetable fats. Moreover, it was shown that Py‐MS offers the possibility of detecting the technological treatment (deodorization and alkalization) of the cocoa butter. This work was extended to the analysis of cocoa masses, consisting of cocoa butter and cocoa powder, however, it was not possible to conclude whether the discrimination of the cocoa masses was obtained because of different geographical origin or because of specific sensory properties. © 1998 John Wiley & Sons, Ltd.

Ethanol/water (7:3) extracts of the plant speciesAnthriscus sylvestrispossess antioxidant activity. Separation and identification of antioxidant components by thin-layer and column chromatography and spectral analysis demonstrated that quercetin and apigenin appeared to be the main flavonoid species inAnthriscus sylvestris. Rutin was one of the major quercetin glycosides. Structures of the isolated compounds were determined by infrared and1H nuclear magnetic resonance spectroscopies. Ethanolic extract (70%) ofA. sylvestrisshowed concentration-dependent, strong antioxidant activity as determined by the Schaal Oven test of lard at 60°C. Rancimat analysis at 100°C showed that the antioxidant activity of 70% ethanolic extract ofA. sylvestriswas superior to quercetin, apigenin, or a tocopherol mixture.

Zusammenfassung: An unterschiedlich groen, wrfelfrmigen Fichtenvollholzproben wurden fr verschiedene Jahrringlagen die Druckscherfestigkeiten in Faserrichtung ermittelt. Von aus jeweils einer Kantel geschnittenen Proben wiesen die kleineren die hheren Druckscherfestigkeiten auf; in tangentialer Scherebene fanden sich die geringeren, in radialer die hheren Werte. Verschieden groe Vollholzproben aus einer Partie Fichtenholz hatten nahezu dieselben Druckscherfestigkeiten. Einzelergebnisse aus Tests mit verklebten Proben aus Brettlamellen waren sehr differenziert; die Gesamtmittelwerte der Druckscherfestigkeiten von groen und kleinen Proben unterschieden sich nicht. Furnierschichtholzproben zeigten dagegen einen deutlichen Einflu der Prfkrpergre. Versuche an Proben aus verklebten Brettlamellen besttigten dies. Kleinere Druckscherproben waren mittig zentriert, direkt hinter groen Proben entnommen worden: die kleineren Proben wiesen immer die hheren Druckscherfestigkeiten auf. Ein Rundversuch bei drei Forschungsinstituten ergab sehr gut bereinstimmende Absolutwerte.

Pyrolysis-mass spectrometry (Py-MS) is an analytical fingerprinting technique that, coupled with suitable multivariate data analysis procedures, offers a rapid method for the characterization of cocoa butters. Our results indicate this technique is capable of discriminating cocoa butters according to different geographical areas (America, Africa, Asia), independent of the different technological treatment (deodorization, alkalization) during production or the presence of other vegetable fats. Moreover, it was shown that Py-MS offers the possibility of detecting the technological treatment (deodorization and alkalization) of the cocoa butter. This work was extended to the analysis of cocoa masses, consisting of cocoa butter and cocoa powder, however, it was not possible to conclude whether the discrimination of the cocoa masses was obtained because of different geographical origin or because of specific sensory properties. © 1998 John Wiley & Sons, Ltd.

Abstract: Ethanol/water (7∶3) extracts of the plant speciesAnthriscus sylvestris possess antioxidant activity. Separation and identification of antioxidant components by thin-layer and column chromatography and spectral analysis demonstrated that quercetin and apigenin appeared to be the main flavonoid species inAnthriscus sylvestris. Rutin was one of the major quercetin glycosides. Structures of the isolated compounds were determined by infrared and1H nuclear magnetic resonance spectroscopies. Ethanolic extract (70%) ofA. sylvestris showed concentration-dependent, strong antioxidant activity as determined by the Schaal Oven test of lard at 60C. Rancimat analysis at 100C showed that the antioxidant activity of 70% ethanolic extract ofA. sylvestris was superior to quercetin, apigenin, or a tocopherol mixture.