Microbial Community and Metabolite Dynamics During Soy Sauce Koji Making

作者：Guiliang Tan, Min Hu, Xiangli Li, Xueyan Li, Ziqiang Pan, Mei Li, Lin Li, Yi Wang, Zi-Yi Zheng · 发表于：Frontiers in Microbiology · 年份：2022 · DOI：10.3389/fmicb.2022.841529 · 被引用次数：36 · 研究领域：Probiotics and Fermented Foods、Fermentation and Sensory Analysis、Biochemical Analysis and Sensing Techniques

Koji making is a pre-fermentation stage in soy sauce manufacturing that impacts final product quality. Previous studies have provided valuable insights into the microbial species present in koji . However, changes in microbial community functional potential during koji -making are not well-known, nor are the associations among microbial populations and flavoring characteristics. In the present study, we investigated the succession of microbial communities, microbial community functional potential, metabolite profiles, and associations among microbial community members/functions with metabolites during koji making using shotgun metagenomic and metabolomic analyses. Firmicutes , Proteobacteria , and Ascomycota were identified as the most abundant microbial phyla in early koji making (0–12 h). Aspergillus (fungi) and Weissella (bacteria) exhibited marked abundance increases (0.98–38.45% and 0.31–30.41%, respectively) after 48 h of fermentation. Metabolite analysis revealed that aspartic acid, lysine, methyl acetate, isovaleraldehyde, and isoamyl alcohol concentrations increased ∼7-, 9-, 5-, 49-, and 10-fold after 48 h of fermentation. Metagenomic profiling demonstrated that koji communities were dominated by genes related to carbohydrate metabolism and amino acid metabolism, but functional profiles exhibited marked shifts after 24 h of fermentation. The abundances of genes within the categories of carbohydrate and amino acid metabolism all increased during koji making, except fo...