酱香型白酒四轮次堆积发酵微生物群落分布规律及其来源分析OA

This research centers on the spreading and stacking fermentation process of Jiangxiangxing Baijiu,with the aim of elucida-ting the distribution patterns of the microbial structure and identifying their sources.Stacked fermented grains,Daqu,and environmental samples from the fourth-round production were utilized as research materials.High-throughput sequencing,gas chromatography,and vari-ous data analysis methods were employed to conduct this study.Results demonstrated that dominant bacteria,including Bacillus,Kroppen-stedtia,Thermoactinomyces,and Virgibacillus,maintained their dominance throughout both the spreading and stacking processes.These bacteria,which were crucial during the stacking fermentation stage,started to accumulate during the spreading process.Similarly,Pichia,the absolute dominant fungus that played a vital role in the stacking process,was also gathered during the spreading stage.Regarding flavor substances,the total content of flavor compounds increased significantly during the spreading process,particularly acidic substances.Dur-ing the stacking fermentation,the contents of aldehydes and acids decreased,while the amount of alcohols increased.A significant correla-tion was observed between microorganisms and flavor substances.For instance,acetic acid was significantly associated with multiple micro-organisms.In the environmental microbial community,bacteria and fungi exhibited distinct compositional characteristics,and some of them were closely related to the microorganisms in the fermented grains.The inter-group difference analysis indicated that the fermented grains during the stacking process had high metabolic activity in multiple pathways.Microbial traceability analysis revealed that in the early stage of spreading,the bacteria and fungi in the fermented grains were strongly influenced by tools.After adding Daqu,it became the primary source of microorganisms.During the stacking process,fungi mainly originated from tools and the ground,and the contribution from work-ers was minimal.This study has clearly defined the dynamic changes and sources of microorganisms during the spreading and stacking fer-mentation process of Jiangxiangxing Baijiu,thereby providing a solid theoretical foundation for optimizing ecological brewing.