Tibetan Tea Drives Baijiu Flavor Formation via Microbial Niche Modulation in Daqu: A Multi-Omics Study

Interest in using Tibetan tea for fermented food production has increased due to its bioactive components and distinctive flavor characteristics. However, its application in Daqu prepared with Tibetan tea remains limited. This study investigated the effects of Tibetan tea addition on Daqu fermentation and Baijiu flavor formation using integrated microbiome and metabolome approaches. High-throughput sequencing, GC-MS, free amino acid analysis, electronic sensory analysis, and correlation network analysis were performed to characterize microbial and metabolic changes. Compared with wheat Daqu (WD), Tibetan tea Daqu (TD) showed higher microbial richness and enhanced fermentation performance (p < 0.05), with enrichment of functional microorganisms including Sphingobium, Komagataella, and Cyberlindnera, which were associated with enzyme activities and flavor precursor formation. Tibetan tea Daqu Baijiu (TDB) exhibited distinct metabolic profiles, with increased levels of esters, acids, terpenes, and free amino acids, contributing to a flavor profile characterized by ester aroma with sweet, umami, woody, and tea aroma characteristics. Correlation analysis revealed that Tibetan tea-driven microbial restructuring was linked to phenylalanine metabolism, esterification, and phenolic transformation pathways. These findings link raw materials, microbiota, and flavor formation, providing a basis for targeted Baijiu design.