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Capillary gas chromatographic analysis of aroma extracts obtained by simultaneous distillation-extraction from yellow passion fruits (Passiflora edulis f. flavicarpa) using a flame photometric detector revealed the presence of previously unreported sulfur-containing volatiles. 3-Mercaptohexanol and the acetates, butanoates, and hexanoates of 3-mercaptohexanol and 3-(methylthio)hexanol, respectively, were identified by comparison of chromatographic and mass spectral data with those of synthesized reference compounds.

The formation of volatile C8 components and less volatile C10 (Cn) oxo and hydroxy acids was investigated in fresh mushrooms (Agaricus campestris). The components were isolated from the mushrooms by distillation-extraction and liquid-liquid extraction and analyzed by capillary gas chromatography-mass spectrometry. Further characterization was made by infrared spectroscopy, NMR spectroscopy, chemical reactions, and Me3Si derivatizations. After addition of linoleic and linolenic acids, the following components were identified for the first time in mushrooms: (Z)-2-octenal, (Z)-l,5-octadien-3-one, (Z)-l,5-octadien-3-ol, (Z,Z)-2,5-octadienal, and (Z,Z)-2,5-octadien-l-ol (partly showing intensive mushroom-like odors). 10-Oxodecanoic acid, 10-hydroxydecanoic acid, 10-oxoundecanoic acid, 10hydroxyundecanoic acid, 10-oxo-8-decenoic acid, 10-hydroxy-8-decenoic acid, 9-oxodecanoic acid, and 9-hydroxydecanoic acid were characterized as enzymatic products from linoleic acid.

N-Substituted pyrroles (1), 2-furaldehyde (2), and N-substituted 2-formylpyrroles (3), formed in pentose (hexose) Maillard systems, were identified as components of extraordinary polycondensation activity. The polycondensation was studied in model experiments with 2), and N-(2-methoxycarbonylethyl)pyrrole (1b)/2-furaldehyde (2), respectively. MALDI-TOF-MS spectra indicated regular oligomers of up to 15-30 methine-bridged N-methyl(or N-2-methoxycarbonylethyl)pyrroles. With participation of aldehyde 2, furan rings instead of pyrrole rings were incorporated. The oligomers 5-11 were isolated and identified by MS and NMR techniques. A complementary experiment with N-methyl-2-[ 13 C]formylpyrrole ([ 13 CHO]-3a)/N-methylpyrrole (1a) was performed. The relevance of the new (type II) melanoidin-like oligomers/polymers in Maillard reactions is discussed and, in conclusion, a corresponding structure for native melanoidins is proposed. The oligomers 5, 6, 8, and 9 were tested for antioxidative activity in an iron(III) thiocyanate assay. Keywords: Model compounds for melanoidins; pyrroles from pentoses and hexoses; β-dicarbonyl pathway of the Maillard reaction; polycondensation of N-methylpyrrole with N-methyl-2-formylpyrrole (N-methyl-2-[ 13 C]formylpyrrole) or 2-formylfuran; polycondensation of N-(2-methoxycarbonylethyl)pyrrole with N-(2-methoxycarbonylethyl)-2-formylpyrrole or 2-formylfuran; MALDI-TOF-MS analysis of melanoidin-like oligomers/polymers; antioxidative activity of oligomeric model compounds

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