Dynamics of microbial community during the extremely long‐term fermentation process of a traditional soy sauce

• Published in: Journal of the science of food and agriculture Vol. 97; no. 10; pp. 3220 - 3227
• Main Authors: Yang, Yang, Deng, Yue, Jin, Yulan, Liu, Yanxi, Xia, Baixue, Sun, Qun
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.08.2017; John Wiley and Sons, Limited
• Subjects: Abundance; Bacteria - classification; Bacteria - genetics; Bacteria - isolation & purification; Bacteria - metabolism; Biodiversity; Breweries; Brewing; Cluster analysis; Clustering; Communities; Community structure; Cultural heritage; Cultural resources; Dynamics; Fermentation; Flavor; Glycine max - metabolism; Glycine max - microbiology; Klebsiella; long‐term fermentation; microbial diversity; Microbiomes; Microorganisms; PCR‐DGGE; Relative abundance; Soy Foods - analysis; Soy Foods - microbiology; Soy sauce; Starter cultures; Time Factors; traditional manufacturing; PCR-DGGE; traditional manufacturing; soy sauce; microbial diversity; long-term fermentation
• ISSN: 0022-5142; 1097-0010
• DOI: 10.1002/jsfa.8169

BACKGROUND Soy sauce produced by long‐term natural fermentation is a traditional specialty in Asia, with a reputation for superior quality and rich flavour. In this study, both culture‐dependent and culture‐independent approaches were used to investigate the microbial diversity and community dynamics during an extremely long‐term (up to 4 years) natural fermentation of Xianshi Soy Sauce, a national intangible cultural heritage. RESULTS Genera of Bacillus, Aspergillus and Cladosporium were detected by both methods above. The relative abundance of the genera Bacillus and Weissella was significantly higher in the late stage than in the early one, while the genera Klebsiella and Shimwellia were opposite (P < 0.05). For microbial community structure, subsequent analyses showed that obvious changes occurred with fermentation time, while there was a fair homogeneousness among samples of the same year, especially during the late fermentation stage. CONCLUSIONS The clustering analysis tended to separate the fermented mashes of the 4th year from the earlier stages, suggesting the necessity of the long fermentation period for developing distinctive microbiota and characteristic quality‐related compounds. This is the first report to explore the temporal changes in microbial dynamics over a period of 4 years in traditional fermentation of soy sauce, and this work illustrated the importance of isolation of appropriate strains to be used as starter cultures in brewing processes. © 2016 Society of Chemical Industry