Correlation between bacterial community succession and propionic acid during gray sufu fermentation

•Monitor the changes of PYR, FUM and PA content in the fermentation process.•Bacterial community succession during the fermentation of gray sufu was tracked.•Dominant bacteria changes from Fusobacterium to Lactobacillus during fermentation.•Microbial interaction affects the metabolism of Propionibacterium.•Lactobacillus could be the key factors to reduce PA content in gray sufu. In order to explore the correlation between the production of propionic acid (PA) and the succession of bacterial community during the fermentation of gray sufu, high-throughput sequencing and HPLC (High Performance Liquid Chromatography) were used to monitor the changes of bacterial community and metabolite content. The abundance and metabolite concentration of Propionibacterium increased rapidly in the early stage of fermentation. In the middle stage, the abundance of Lactobacillus began to increase, while the pH decreased rapidly. In the late stage, the concentration of PA began to decrease, but it remained at a high level at the end of fermentation. Correlation analysis showed that Lactobacillus and Bacillus had a strong negative correlation with PA and its precursor. The results showed that Fusobacterium, Providencia, Lactobacillus and Bacillus could be the key factors to reduce the PA content. This study provides a new idea for the quality control of traditional fermented food.