Bacterial diversity and its correlation with sensory quality of two types of zha-chili from Shennongjia region, China

In the Shennongjia region of China, two types of zha-chili with distinct flavors exist: the first type (P zha-chili) uses a significant amount of chili pepper but no potato, while the other (PP zha-chili) contains a smaller amount of chili pepper but a proportion of potato. In order to investigate the bacterial diversity and sensory properties of these two types of zha-chili, this study employed a combination of amplicon sequencing, culture-based methods, and sensory technology. The results of the study showed statistically significant differences (P < 0.05) in bacterial diversity and communities between the two types of zha-chili. In particular, four dominant lactic acid bacteria (LAB) genera - Lactiplantibacillus, Lactococcus, Leuconostoc, and Weissella - were significantly enriched in PP zha-chili. The findings suggest that the proportions of chili pepper and potato can influence the bacterial diversity and content of LAB, with a higher proportion of chili pepper potentially inhibiting the growth of harmful species within the Enterobacteriaceae family. The study also used culture-based methods to identify the most dominant bacteria in the zha-chili samples as Lactiplantibacillus plantarum group, Companilactobacillus alimentarius, and Lacticaseibacillus paracasei. Correlation analysis indicated that LAB likely plays a significant role in shaping the aroma profile of zha-chili, with Levilactobacillus, Leuconostoc, Lactiplantibacillus, and Lactococcus showing correlation with E-nose sensory indices. However, these LAB were not significantly correlated with the taste properties of zha-chili. The study provides new insights into the influence of chili pepper and potato on the microbial diversity and flavor properties of zha-chili, and also presents potential LAB isolates for future research on zha-chili.