Analysis of microbiota in Hainan Yucha during fermentation by 16S rRNA gene high‐throughput sequencing

Yucha is a type of spontaneously fermented food consumed in the Hainan province of China. In the current study, bacterial microbiota was analyzed by 16S rRNA High-throughput Gene Sequencing and changes in titratable acidity, as well as quantity of lactic acid bacteria, were monitored during the fermentation process of Yucha. We observed that bacterial diversity underwent more rapid changes in the first 4 weeks of the fermentation process. Lactococcus and Lactobacillus were the dominant microbial populations present during the whole process of Yucha fermentation, which rapidly proliferated accompanied by a decline in other bacterial groups, resulting in a significant increase in titratable acidity of Yucha. Furthermore, it is worth noting that there were some microbial populations with a relatively low abundance, such as Vibrio, Acinetobacter, and Enterococcus, which could possibly have a negative effect on the biosafety aspects of Yucha consumption. Practical applications Fermentation is a key step in Yucha production. In this study, a change in the population of bacteria in Yucha during fermentation was monitored, dominant bacteria present in Yucha were determined, and the profile of the dominant bacteria in the fermentation process was obtained. In addition, some bacteria that may have a negative impact on Yucha were detected. These results may prove to be useful for large-scale production of Yucha and improvement of its biosafety.