Identification and sensory characterization of volatile flavor compounds in sesame seed oil

Voltile flavor compounds in sesame seed oil were investigated. Commercially processed sesame seed oil was steam distilled under reduced pressure, and volatiles fr om the distillate were separated by an adsorptive column method. Among 171 individual peaks detected, 134 peaks were definitely or tentatively identified by analysis of mass spectra and modified Kovats indices. To elucidate the compounds directly contributing to the characteristic flavor, the odor concentrate was fractionated by silica gel thin-layer chromatography and preparative gas chromatography. As a result, 1-(5-methyl-2-furanyl)-1-propanone, 3-formylthiophene, 2-propyl-4-methylthiazole, 2-ethyl-4-methyl-1H-pyrrole, 2-ethyl-6-methylpyrazine, 2-ethyl-5-methylpyrazine, 4,5-dimethylisothiazole, 4,5-dimethylthiazole, 2,6-diethylpyrazine, 2-ethyl-2,5-dimethylpyrazine, 1-(2-pyridinyl)ethanone, and 1-(1-methyl-1H-pyrrol-2-yl)ethanone were considered to be principal contributors of sesame seed oil flavor.