Abstract
Fermented cowpeas, a traditional Chinese pickle, are valued for their characteristic taste and nutrition. This study examined flavor evolution and microbial dynamics during fermentation and storage via physicochemical analysis, volatile and nonvolatile compounds profiling, and microbial community assessment. 21 and 18 key discriminatory volatiles (VIP > 1) were identified via GC-MS and GC-IMS in cowpea samples, respectively. Multivariate analysis indicated that changes in flavor quality resulted from the combined effects of lactic acid, umami, and sweet amino acids, and 12 key aroma-active compounds (VIP > 1 and OAV > 1). Five core functional microorganisms (Debaryomyces, Companilactobacillus, Levilactobacillus, Chromohalobacter, and Microbacterium) were identified. Pearson correlation analysis revealed positive associations among these microorganisms and lactic acid, amino acids (Glu, Asp, Ala), and several key aroma-active compounds but negative associations with spermidine, tartaric acid, and Asn. These findings link microbial metabolism to flavor development in fermented cowpeas, revealing insights into fermentation-driven flavor modulation.