Analysis on the difference of volatile flavor compounds of the first round base liquor of sauce-flavor Baijiu with different years

Using the first round base liquor of sauce-flavor (Jiangxiangxing) Baijiu with different years as research objects, the volatile flavor compounds were analyzed by HS-SPME-GC-MS technology. The model was constructed using principal component analysis (PCA) and orthogonal partial least square method-discriminant analysis (OPLS-DA), and the differential flavor compounds of the first round base liquor of sauce-flavor Baijiu with different years were screened based on variable importance in the projection (VIP) values and variance analysis P values. The differences of volatile flavor compounds in the first round base liquor were analyzed combined with sensory quantitative descriptive analysis (QDA). The results showed that the scores of floral, fruity, sour, and grain aromas in the first round base liquor were higher, and the scores of sour and grain aromas decreased with the increase of aging years, while the scores of fruity, floral aromas and aftertaste increased with the increase of aging years. A total of 156 volatile flavor compounds were detected in the first round base liquor, including 12 acids, 44 esters, 13 aldehydes, 27 alcohols, and 60 others. The first round base liquor could be distinguished by PCA and OPLS-DA. A total of 89 differential flavor compounds (VIP>1, P<0.05) were selected. Among them, 10 kinds of substances including benzaldehyde, 4-undecanone, 1-octanol, propyl octanoate, butyl acetate, ethyl isovalerate, 3-octanol, heptanal-2-ethylacetal, 2-pentyl butyrate, and 2-nonanol were potential key differential compounds that led to the difference of the first round base liquor of sauce- flavor Baijiu with different years.