Dynamic changes in the bacterial community in Moutai liquor fermentation process characterized by deep sequencing

Microbes are the major producers of alcohol and aromatic compounds in alcohol beverages. It is believed that, in addition to production techniques and grains, different micro-ingredient compositions yield variations in aromas and tastes. The bacterial communities of the three key phases from Moutai liquor production were profiled with the Illumina sequencing platform. A total of 54 bacterial families were detected and the microbial structure showed clear differences among samples. In the starter-making phase, Leuconostocaceae and Enterococcaceae dominated the shaping stage, and Bacillaceae dominated the mature starter and ripening stages. In the latter two phases, Bacillaceae and Lactobacillales dominated in the early stage of stack fermentation and the anaerobic stage of pit fermentation, respectively. Most of the important microbes (approximately 26 families) might have originated from the starter and greatly affected the bacterial structure of the samples during the early stages of stack fermentation. Production techniques and environmental factors, such as temperature and oxygen, also shaped the unique bacterial composition during different phases.