Effect of antioxidants on the volatiles of roasted sesame seeds

The aroma concentrates of roasted sesame seeds free from antioxidants (sesamin-sesamolin) as well as of roasted defatted sesame seeds mixed with sesamin-sesamolin were fractionated into neutral-acidic and basic fractions. The volatile components of each fraction were identified by the retention times of the authentic samples in gas-liquid chromatography-mass spectrometry. The major changes in components of the neutral-acidic fraction of the sesamin-sesamolin free sample were the amounts of 2,4-undecadienal (32.59%) and 2,4,6-dodecatrienal (18.61%) compared to those of the whole seeds (49.44% and 6.9%, respectively). However, irregular changes were observed for the pyrazine derivatives of the basic fraction. The predominance of the nutty flavor, thus, might be due to the increase of some individual pyrazine derivatives at the expense of some furan derivatives.