Evaluating the flavor and divergent bacterial communities in corn-based zha-chili

Abstract

Zha-chili is a naturally fermented traditional food from central southern China. Corn-based zha-chili is one of the most popular varieties with a special flavor. To investigate its distinct microbiome, corn-based zha-chili samples were collected and investigated using both high-throughput sequencing and culture-dependent method. Subsequently, E-nose and E-tongue sensors were used to evaluate the overall sensory profile. We found that the bacterial communities present in zha-chili samples from the two regions were significantly different (P < 0.05). Companilactobacillus, Lactiplantibacillus, and Corynebacterium were found to be the dominant genera common to samples from both regions. Among these, lactic acid bacteria were the most dominant. Biomarker genera were Ligilactobacillus, Lactobacillus, and Levilactobacillus (Huaihua) and Pantoea, Lactiplantibacillus, and Weissella (Songtao). Using culture-dependent methods, the most dominant genus Companilactobacillus was found to comprise Companilactobacillus alimentarius and Companilactobacillus futsaii. The sensory profile was also characterized. This indicated that zha-chili from the two regions could be discriminated by sourness and aftertaste-B (E-taste), and W1C, W3C, W5C, W1S, W2S, W5S, and W2W (E-nose). Correlation analysis suggested that the dominant genera might not affect the aroma quality of corn-based zha-chili, whereas they were related to taste quality. Levilactobacillus and Ligilactobacillus were positively correlated with the characteristic taste indices and negatively correlated with the off-flavor indices. Another dominant genus, Kocuria was positively correlated with umami and richness (P < 0.05). Our results could provide a basis for supporting zha-chili production and help the isolation of appropriate lactic acid bacteria from corn-based zha-chili.