Differences in flavor characteristics of rounds of Sauce-based Baijiu based on GC-IMS, GC-MS, and electronic tongue

Abstract

The volatile flavor and metabolic pathway differences of rounds of Sauce-based Baijiu (RSBs, R-1∼R-7) were analyzed using HS-GC-IMS and HS-SPME-GC-MS. Firstly, 18 (R-1, R-2, R-4, R-6, and R-7), 17 (R-3), and 19 (R-5) characteristic flavor compounds were identified based on GC-IMS by the relative odor activity value (ROAV) analysis. Secondly, a total of 751 metabolites were identified using GC-MS, and the differential metabolites were screened for pathway enrichment analysis by variable importance in projection (VIP) > 1 combined with fold change (FC) ≥ 2 or ≤ 0.5. The results demonstrated that unsaturated fatty acid metabolism, fatty acid metabolism, terpene metabolism, and secondary metabolite biosynthesis pathways were the most significant metabolic pathways influencing the flavor of basic baijiu, which primarily resulted in alterations in the composition and concentration of metabolites, including fatty acids and terpenes. Furthermore, RSBs demonstrated distinctive taste attributes, the addition of R-1 was found to markedly influence the astringency of baijiu (p < 0.05), while no notable impact was observed on the acidity or aftertaste. This study elucidates the flavor characteristics of RSBs, which provides a reference for the flavor quality regulation and blending of baijiu.