Aroma of roasted sesame oil: Characterization by direct thermal desorption-gas chromatography-olfactometry and sample dilution analysis

Aroma constituents of roasted sesame seed oils were isolated and identified by direct thermal desorption-gas chromatography-olfactometry (DTD-GCO) and DTD-GC-mass spectrometry (MS). Sample dilution analysis (SDA), in which decreased volumes of oil were sequentially analyzed by DTD-GCO, was used to indicate predominant odorants. Forty-nine odorants were detected by SDA with detection volumes (DVs) from 8 to 1000 nL. Those detected with DVs from 8 to 40 nL were 1-octen-3-one, 4,5-epoxy-(E)-2-decenal, 2-acetyl-3-methylpyrazine, 2-methoxyphenol, 2,3-diethyl-5-methylpyrazine, 3-methylbutanal, (E)-2-nonenal, 2-methoxy-4-vinylphenol, and an unidentified compound (plastic aroma note). Results of quantitative analysis were in general agreement with those of SDA.