Exploring core functional microbiota related with flavor compounds involved in the fermentation of a natural...

This study aimed to explore the core functional microbiotas related to flavor compounds involving in a naturally fermented soybean curd (plain sufu). Properties such as physicochemical parameters, flavor compounds (17 free amino acids, 21 fatty acids, and 14 aroma volatiles) and microbiota profiles were investigated, and their correlations were explored at 8 stages during production. Results from principal component analysis, multiple factor analysis, and partial least squares-discrimination analysis showed that these properties varied significantly in the eight stages. Furthermore, based on Pearson correlation coefficients and Variable importance for predictive components values between the microbiota profiles and flavor compounds, nine bacterial (Bacillus, Enterobacter, Lactobacillus, Sphingobacterium, Stenotrophomonas, Tetragenococcus, Trabulsiella, Unclassified, and Weissella) and six fungal (Alternaria, Sterigmatomyces, Actinomucor, Fusarium, Debaryomyces, Candida) genera were identified as core functional microbiotas significantly affecting the production of flavor compounds during the natural production. Overall, this study provided a comprehensive description of the dynamic changes of physicochemical parameters, flavor compounds, and microbiota profiles throughout the natural production of plain sufu. The similarities and variations among different stages, as well as correlation between flavor compounds and microbiotas would help to understand the mechanism of plain sufu production, and further to enhance the quality control of plain sufu.