Bioturbation effect of High -yield pyrazine strain on the microbial community and flavour metabolites of fortified Daqu

In order to comprehensively explore the regulatory effect of bioturbation on the assembly and overall metabolic characteristics of Daqu microbial community, and also to increase the health factors of Baijiu. This study used metatranscriptomics and metabolomics to investigate the microbial community composition, physical and chemical properties, and overall metabolic profile of Daqu before and after bioturbation. The results showed that after bioturbation, the moisture content, amino acid nitrogen content, starch content and acidity of Daqu increased significantly. The symbol microorganisms of Daqu have also changed significantly, from the original Aspergillus chevalieri, Aspergillus cristatus, Aspergillus glaucus, Aspergillus ruber, Aspergillus wentii and Rasamsonia emersonii to Paecilomyces varioti, Trichomonascus ciferrii and Staphylococcus gallinarum. Correlation analysis and integration pathways showed that the altered microbial community abundance also promoted the metabolism of starch, ethanol, fatty acids and pyrazines, resulting in a significant increase in the liquefaction and saccharification power of Daqu, as well as the content of some volatile and non-volatile metabolites, with pyrazines generally increasing by 24.