Headspace gas analysis of volatile compounds of light and deep roasted sesame seed oil

Volatile compounds in the headspace gas of light and deep roasted sesame seed oil were analyzed by gas chromatography and gas chromatography-mass spectrometry. The present method resulted in good reproducibility (<6.6% as a relative standard deviation) in the determination of individual volatile components. About 64 compounds, including 30 heterocyclic compounds, 7 aliphatic aldehydes, 11 ketones, and 16 miscellaneous compounds, were identified. Peak area percentages of 2-methylpropanal, 2-butenal, 2- and 3-methylbutanal, 2-propanone, 2-butanone, 3-methyl-2-butanone, 2,3-butanedione, 2- and 3-methylfuran, and 2,5-dimethylfuran, all of which could not be detected by steam distillation and column adsorptive concentration (previous method), increased in deep roasted oil. Hexanal decreased from 6.13% to 2.55% in deep roasted oil. Compared with the previous method, pyridine, thiophenes, and sulfides could be detected only by the present method, but unsaturated aliphatic aldehydes could not.