Volatile Profiles of 13 Foxtail Millet Commercial Cultivars (Setaria italica Beauv.) from China

The volatile components from 13 commercially valuable foxtail millets from China were investigated by means of gas chromatographymass spectrometry combined with simultaneous distillation extraction. A total of 52 volatile compounds were identified in all of the samples: 19 aldehydes, 5 alcohols, 10 ketones, 9 hydrocarbons, 6 benzene derivatives, and 3 others. Here, 23 common constituents were found in all samples. Aldehydes were the predominant volatile components in various cultivars. The importance of each volatile was assessed on the basis of odor thresholds and odor activity values (OAVs). Here, 35 volatile compounds were described using aroma character, and 24 volatile compounds were found to be odor-active compounds. Another 11 common constituents were found in all samples. The components with the highest OAVs in most cultivars were (E)-2-nonenal and (E,E)-2,4-decadienal. Most of the other aldehydes also had high OAVs. Some of the ketones, alcohols, benzene derivatives, and other compounds were found to contain an odor-active compound in several cultivars of foxtail millet. Principal component analysis was employed to evaluate the differences among cultivars. The results demonstrated that the volatile profile based on the OAVs of aroma compounds enabled good differentiation of most cultivars.