Multiomics analysis of microbial succession and flavor formation mechanism during the fermentation process of Maotai-flavour Baijiu

This study employed metagenomics and metabolomics techniques to investigate the complex relationship between microbial succession and the formation of flavor compounds during the fermentation process of Maotai-flavour Baijiu. Results demonstrated that stacking fermentation, characterized by Weissella , Pichia , and Aspergillus , which secreted amylases and proteases to hydrolyze starch and proteins. Pitting fermentation facilitated the enrichment of anaerobic microbes such as Acetilactobacillus and Pichia , significantly promoting the synthesis of key flavor compounds, including esters, alcohols, and acids, through Glycosyltransferase and Esterification activities. Volatile compound analysis revealed distinct stage-specific profiles, with acids, alcohols, and esters accumulating predominantly in pit fermentation. These findings elucidate the stage-specific microbial metabolic networks and synergistic mechanisms underlying flavor formation, providing a scientific basis for optimizing traditional Baijiu fermentation processes. • MT is dominated by Saccharomyces and Lactobacillus , while RH shows microbial diversity. • MT has high ester, JS features elevated aldehydes, reflecting regional sensory. • Volatile substances mainly accumulate during pitting fermentation.