Abstract: In this study, 16S rRNA high-throughput sequencing was used to study the bacterial community succession in fish sauce during its fermentation process. The results showed that number of bacterial species in fish sauce increased first, peaking (312 species) at month 6, and then decreased with prolonged fermentation time. Less abundant bacterial diversity and a smaller difference among the bacterial communities were observed from month 6 to 12 of fermentation. Firmicutes and Proteobacteria were the most dominant phyla during the whole fermentation process. Haloanaerobium was the most predominant genus, and its relative abundance increased first and then decreased with increasing fermentation time. The relative abundances of Photobacterium, Tetragenococcus and Halomonas were significantly increased during the mid to late fermentation stages compared with those at month 0. At the end of the 12-month fermentation period, Halomonas became the dominant genus. Gas chromatography-mass spectrometry (GC-MS) was used to study the volatile flavor components in fish sauce during the fermentation process. A total of 54 volatile flavor components including aldehydes, alcohols, ketones, esters, hydrocarbons, acids and nitrogen compounds were detected, and 9 key volatile flavor compounds were identified according to their odour activity value (OAV) ( ≥ 1). Pearson’s correlation analysis showed that Halanaerobium and Halomonas had a significant correlation with the changes in major volatile compounds. These results suggest that the bacterial community structure has an important influence on the formation of volatile flavor components in Chinese fish sauce.

Key words: Chinese fish sauce, bacterial community, bacterial diversity, volatile flavor, high-throughput sequencing