Analysis of the Bacterial Communities in Two Liquors of Soy Sauce Aroma as Revealed by High-Throughput Sequencing of the 16S rRNA V4 Hypervariable Region

Abstract

Chinese liquor is one of the world's oldest distilled alcoholic beverages and an important commercial fermented product in China. The Chinese liquor fermentation process has three stages: making <i>Daqu</i> (the starter), stacking fermentation on the ground, and liquor fermentation in pits. We investigated the bacterial diversity of Maotai and Guotai <i>Daqu</i> and liquor fermentation using high-throughput sequencing of the V4 hypervariable region of the 16S rRNA gene. A total of 70,297 sequences were obtained from the <i>Daqu</i> samples and clustered into 17 phyla. The composition of the bacterial communities in the <i>Daqu</i> from these two soy sauce aroma-style Chinese liquors was the same, although some bacterial species changed in abundance. Between the <i>Daqu</i> and liquor fermentation samples, 12 bacterial phyla increased. The abundance of <i>Lactobacillus</i> and <i>Pseudomonas</i> increased in the liquor fermentation. This study has used high-throughput sequencing to provide new insights into the bacterial composition of the Chinese liquor Daqu and fermentation. Similarities in the distribution of bacteria in the soy sauce aroma-style Chinese liquors <i>Daqu</i> suggest that the abundance of bacteria might be generally concerned to other liquor.