Abstract: In this study, the culturable bacterial communities of Daqu and brewing environment samples of Moutai-flavor Baijiu in Maotai town were studied through traditional microbial isolation and screening and molecular identification. A total of 1 370 isolates belonging to 5 phyla, 28 genera and 59 species of bacteria were obtained, including Bacillus solani, B. gottheilii, B. paralicheniformis, Brevibacillus agri, Pseudomonas xanthomarina, Lelliottia nimipressuralis, Aureimonas sp., Sphingobacterium daejeonense, Oceanobacillus indicireducens, Cronobacter sakazakii, Mixta gaviniae, Paraburkholderia fungorum, Viridibacillus arvi and Atlantibacter hermannii, which have been rarely detected during Moutai-flavor Baijiu brewing. Analysis of the distribution frequency and dominance of bacteria showed that Bacillus, Lysinibacillus, Staphylococcus and Micrococcus were the core culturable bacteria in Daqu, while Bacillus, Staphylococcus, Micrococcus and Alcaligenes were the core culturable bacteria in the brewing environment, and Bacillus, Staphylococcus and Micrococcus were the culturable core bacteria common to Daqu and environmental samples. The diversity and structure of bacterial flora differed between Daqu and environmental samples for each round of fermentation, while the structure and succession of the main functional bacterial flora remained basically consistent. The dominant bacteria in Daqu and environmental samples could function to metabolize abundant enzyme systems and to strongly adsorb and degrade metal ions. The data of this study provide a basis for research on microorganisms involved in the brewing of Moutai-flavor Baijiu in Maotai town and other areas.

Key words: Moutai-flavor Baijiu; culturable bacteria; microbial diversity; brewing function