Temperature dynamics regulate microbial succession and flavor formation in medium-high temperature Daqu

Microbial metabolism is a key driver in the biosynthesis of food flavor compounds, shaping the aroma and sensory characteristics of fermented products through enzymatic catalysis, substrate conversion, and secondary metabolism. This study investigated the complex relationships among room temperature, functional microorganisms, and characteristic flavor metabolites in medium-high temperature Daqu . Environmental parameters were monitored in the fermentation workshop, and multi-omics analysis revealed that the synergistic control of room temperature and humidity was critical for stable Daqu quality. GC-MS analysis identified four key flavor compounds: 2-methoxy-4-vinylphenol, phenylethyl alcohol, 2,3-butanediol, and tetramethylpyrazine (TTMP). KEGG pathway reconstruction and metatranscriptomics linked functional enzymes to Pichia , Limosilactobacillus , Lichtheimia and Rhizopus . Structural equation modeling（SEM） confirmed that room temperature indirectly regulates flavor formation mainly by affecting the abundance of Pichia . These findings clarify the mechanism of temperature-mediated microbial succession and flavor metabolism in Daqu , offering scientific support for revealing traditional Baijiu fermentation principles, optimizing brewing technology, and improving product flavor quality. • Core functional microbiota dynamics in medium-high temperature Daqu . • GC-MS characterization of signature flavor compounds in Daqu . • Multi-omics reveal microbial contributions to flavor formation. • SEM-based analysis of temperature-microbiota-flavor interactions.