Correlation analysis between microbial community and physiochemical indexes in Daqu for different flavor Baijiu brewing

In this study, the physiochemical indexes of four kinds of Daqu with different flavor type (strong-flavor Daqu HN2, Feng-flavor Daqu FX1, sauce-flavor Daqu LJ1, light-flavor Daqu FQ1) were analyzed. The differences of microbial community composition and structure were analyzed by high-throughput sequencing technology, and the physiochemical indexes and microbial dominant microbes were analyzed by Spearman correlation analysis. The results showed that the saccharification and esterification power of FX1 was the highest, and the liquefaction and fermentation power of FQ1 were the highest. Firmicutes showed higher relative abundance of HN2 and LJ1. Staphylococcus, Pantoea and Virgibacillus had a high relative abundance in HN2, FX1 and LJ11, while Streptomyces had a high relative abundance in FQ1. Correlation analysis results showed that Pantoea and Furfurilactobacillus had significant positive correlation with saccharification power (P<0.01), Companilactyobacillus had significant positive correlation with esterification power (P<0.01). Lactiplantibacillus and Saccharomycopsis had significant positive correlation with fermentation power (P<0.01).