Dynamic changes in the microbial community, flavour components in jiupei of a novel Maotai-Luzhou–flavoured liquor under various daqu blending modes and their correlation analysis

Abstract

Maotai-Luzhou–flavoured jiupei was investigated regarding dynamic changes in its microbial community, accumulation of volatile compounds, physicochemical properties and enzyme activity. The results indicated that Lactobacillus (0.04%–0.97%) and Aspergillus (30.57%–71.02%) were the core genera of the jiupei. Burkholderia, Acetobacter, Kroppenstedtia, Pantoea, Rhizopus, Candida and Thermomyces (relative abundance >0.05%) were the unique dominant genera of fermented grains. Of all the volatile compounds in jiupei, the content of acids, alcohols and esters was the highest. Among these, the alcohol (57.57%) content was the highest, while the acid (0.71%) content was the lowest. Lactobacillus and Aspergillus were closely related to the main flavour substances ethyl acetate (4.37 ± 0.14 mg/kg), ethyl 2-hydroxypropanoate (4.13 ± 0.11 mg/kg), ethyl ester hexanoic acid (29.11 ± 0.11 mg/kg), hexadecanoic acid (0.76 ± 0.03 mg/kg) and 3-methyl-1-butanol (0.91 ± 0.04 mg/kg). Additionally, acidity and cellulase are important factors affecting the composition of flavour substances. This study clarified the relationship between the succession of microbial structure in the fermentation process and environmental factors and provides suggestions for the potential optimisation of Maotai-Luzhou-flavoured liquor production.