Dynamics of quality attributes, flavor compounds, and microbial communities during multi-driven-levels chili fermentation: Interactions between the metabolome and microbiome.

Dynamics and correlations of quality attributes, microbial profiles, and flavor metabolites were systematically investigated during chili fermentation on multi-salinity-driven levels (8/13/18 %). Metabolomic analysis revealed that pre-fermentation contributed to acetic acid (10.16 mg/kg, 65.01 %) and biogenic amines (53.70 mg/kg, 70.43 %). While main- and post-fermentation accumulated lactic acid (48.33 mg/kg, 76.49 %). Metabolome-microbiome interactions revealed that dominant genera mediated by salt levels affected the distribution of 24 differential odorants in 54 aromatic compounds. Enterobacter, Klebsiella, Cronobacter, and Acinetobacter triggered the production of 121 mg/kg biogenic amines and 7 unpleasant flavors. 7 dominant genera including Leuconostoc, Lactococcus, Weissella, Lactobacillus, Candida, Pichia, and Kazachstania were correlated with spicy, fruity, and floral aromas. Interestingly, salt-acid alternation drove succession from Leuconostoc, Weissella, and Lactococcus to Lactobacillus and Pediococcus. Overall, microbial composition and function were metabolism-dependent patterns. These results provide insight into microbial succession and flavor formation during staged fermentation and promote to optimize quality of fermented chili.