Abstract: The aroma-active compounds in five single-grain Chinese Baijiu brewed from different raw materials were detected by gas chromatography-olfactometry-mass spectrometry (GC-O-MS). A total of 22, 23, 20, 18 and 21 aroma-active substances were found in sorghum, wheat, non-glutinous rice, glutinous rice and corn Baijiu, respectively, mainly including esters, aldehydes and alcohols. The main aroma compounds identified were ethyl acetate, ethyl 2-methylbutyrate, 2-n-pentylfuran, ethyl caproate and ethyl octanoate. Nine dominant aroma compounds (with smell intensity equaling or exceeding 4) were detected in sorghum Baijiu, 7 in wheat, non- glutinous rice Baijiu, and corn Baijiu and 5 in glutinous rice Baijiu. The volatile components and aroma-active compounds identified in wheat Baijiu were more than those in the other Chinese Baijiu, and the compounds with high aroma intensity in sorghum Baijiu were more than those in the other Chinese Baijiu, and while those in glutinous rice Baijiu were the fewest. Sensory evaluation indicated that sorghum Baijiu scored highest in ester aroma and overall aroma balance. Wheat Baijiu was characterized mainly by ester aroma, corn Baijiu by corn-like and mellow aroma, and non-glutinous rice and glutinous rice Baijiu by refreshing mouthfeel.

Key words: raw material; Chinese Baijiu; gas chromatography-olfactometry-mass spectrometry; aroma-active compounds; sensory evaluation