Study on the Correlation between Microbial Community Succession and Physicochemical Factors during the Storage of Maotai-flavor Liquor in Daqu at High Temperature

Objective: Through analyzing the physicochemical properties and microbial changes of high temperature Daqu of Maotai-flavored during the storage (0~150 days), the paper aimed at comprehending the aging and maturity law of Daqu. Methods: Based on the traditional cultivable method and high-throughput sequencing technology, the research analyzed the succession law of microbial community structure during the storage of Daqu, and the relationships between physicochemical factors and microorganisms by combining the correlation. Results: The number of cultivable microorganisms showed a trend of first increased and then declined with the increased storage time during the storage. The temperature and saccharification index showed a trend of first increased and then declined, moisture and acidity showed a declined trend with increasing storage time. Meanwhile, the main leading bacteria genus during the storage were Kroppenstedtia, Lactobacillus, Staphylococcus and Enterobacter respectively, the main leading fungus genus were Thermomyces, Trichomonascus and Byssochlamys respectively. There was a complicated relationship between microbial community and physicochemical indicators, of which Bacillus, Kroppenstedtia, Aspergillus and Trichomonascus were positively correlated with temperature, Byssochlamys and Dipodascus were positively correlated with temperature, moisture, acidity and liquefaction power. Thermocycles was negatively correlated with temperature, moisture, and acidity. Conclusion: The research revealed the microbial community composition status and the relationships between physicochemical factors of high-temperature Daqu of Maotai-flavored during the storage, which provided a theoretical reference for further introducing the post ripeness mechanism of high-temperature Daqu of Maotai-flavored.