Diversity and succession of lactic acid bacteria during sesame-flavor liquor fermentation

Abstract:

[Background] Lactic acid bacteria are important in liquor fermentation, and the diversity and succession of lactic acid bacteria have important influence on liquor quality. However, the structure and succession of lactic acid bacteria communities are not clear during sesame-flavor liquor fermentation. [Objective] We studied the diversity and succession of lactic acid bacteria communities during sesame-flavor liquor fermentation for better process control and product quality. [Methods] High-throughput sequencing was used to analyze lactic acid bacteria communities during sesame-flavor liquor fermentation. Biomass of lactic acid bacteria was quantified by real-time qPCR. [Results] Lactic acid bacteria in sesame-flavor liquor fermentation included Weissella, Pediococcus, Lactobacillus, Leuconostoc, and Lactococcus, classified to 43 species. Ten species of lactic acid bacteria were observed higher than 0.5%, including Weissella paramesenteroides, Weissella cibaria, Weissella confuse, Pediococcus pentosaceus, Leuconostoc pseudomesenteroides, Lactobacillus fermentum, Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus acetotolerans and Lactobacillus sp.. In heap-fermentation stage, Weissella was more than half of the total bacteria, followed by Pediococcus and Lactobacillus. Leuconostoc and Lactococcus were present in low numbers. In pit-fermentation stage, Lactobacillus became the predominant bacteria, and the relative abundance of Lactobacillus sp. was up to 80% in the mid and later stage of pit-fermentation. During heap-fermentation and the early stage of pit-fermentation, the biomass of lactic acid bacteria changed little. After 5 days of pit-fermentation, the biomass of lactic acid bacteria increased fast, and reached the maximum at 30 days. [Conclusion] The knowledge of diversity and succession of lactic acid bacteria during sesame-flavor liquor fermentation will help understand the roles of lactic acid bacteria in liquor production with better process control and product quality.