ZHU Shuai, FU Changbiao, PENG Yi, WANG Dongmei, LIU Fayang, LIU Maoqiang, YANG Junjie
To investigate the flavor structural characteristics and discrepancies of round-based base liquors of sauce-flavor (Jiangxiangxing) Baijiu from the Chishui River Basin and northern China, taking the base liquors of the 1st to 7th rounds sauce-flavor Baijiu from three distilleries located in Sichuan, Guizhou and Shandong producing areas as examples, the aroma components were analyzed by direct injection combined with gas chromatography-mass spectrometry. A discriminant model was established via partial least squares-discriminant analysis, and differential aroma compounds were screened according to variable importance in projection (VIP) values. The results showed that a total of 56 aroma compounds were detected in round 1-7 base liquors from various producing areas, consisting of 18 esters, 16 alcohols, 8 acids, 11 aldehydes and ketones, and 3 other compounds, with esters, alcohols and acids dominating the aroma profile, accounting for over 85% of the total aroma content. Among them, the aroma compound structures of base liquors from the 1st and 7th rounds in different producing regions differ significantly from other rounds, while those of the 3rd, 4th, and 5th rounds also show certain differences among the three manufacturers. A total of 31 vital aroma compounds were screened, combined with odor activity value (OAV). Among them, isoamyl acetate, propionic acid, isoamyl alcohol, n-propanol, ethyl acetate, butyl acetate, isovaleraldehyde, acetic acid, 2-methylbutyraldehyde, furfural, isobutyraldehyde, isobutanol, sec-butanol, ethyl decanoate, ethyl lactate and acetaldehyde (VIP > 1) were identified as the key differential aroma compounds in round-based base liquors from different producing areas. These differences were presumably related to variations in brewing processes, geographical environments and microbial community structures among producing regions.