Quality grade of round base liquor of sauce-flavor Baijiu by sensory ranking and multivariate statistical analysis

To provide a method for evaluating the quality grade of sauce-flavor (Jiangxiangxing) Baijiu in this study, Friedman, Multiple Comparison, and Page Statistical tests were used to carry out sensory analysis on 16 sauce-flavor Baijiu samples of different grades from 4 groups, and the flavor components of sauce-flavor Baijiu samples were analyzed by gas chromatography (GC). The different grades of base liquor were distinguished by orthogonal partial least squares discriminant analysis (OPLS-DA). The results showed that there were differences in the sensory characteristics of base liquor from different grades, and the method could achieve the optimal expression of the sensory ranking results of sauce-flavor Baijiu quality grades. A total of 35 volatile flavor components were identified from 16 sauce-flavor Baijiu samples, mainly including alcohols, esters, and aldehydes and ketones. Overall, the types of compounds in Baijiu from different grades were basically similar, but the relative contents were significantly different. The OPLS-DA method could effectively distinguish base liquor of different grades, and based on variable importance in projection value (VIP>1), the isovaleric acid, ethyl decanoate tetramethylpyrazine, and other compounds were screened as the key differential compounds. The sensory ranking combined with multivariate statistical analysis technology was helpful for identifying the quality grade of sauce-flavor Baijiu in an objective, scientific, and efficient way.