The prokaryotic community, physicochemical properties and flavors dynamics and their correlations in fermented grains for Chinese strong-flavor Baijiu production. (October 2021)

• Record Type: Journal Article
• Authors: Hu, Xiaolong; Tian, Ruijie; Wang, Kangli; Cao, Zhenhua; Yan, Peixun; Li, Fuqiang; Li, Xuesi; Li, Shaoliang; He, Peixin
• Is Part Of: Food research international. Volume 148(2021)
• Publication Date: 2021-10
• Subjects: Baijiu -- Fermented grains -- Dynamics of community -- Physicochemical properties -- Flavor; Food -- Analysis -- Periodicals; Food industry and trade -- Periodicals; Food industry and trade -- Canada -- Periodicals; Food Technology -- Periodicals; Food -- Periodicals; Food-Processing Industry -- Periodicals; Aliments -- Industrie et commerce -- Périodiques; Aliments -- Industrie et commerce -- Canada -- Périodiques; Aliments -- Recherche -- Périodiques; Food industry and trade; Canada; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.foodres.2021.110626
• Languages: English
• ISSNs: 0963-9969

Abstract

Graphical abstract: Highlights: The dynamics of physicochemical properties, prokaryotic community and flavors in FGs were comprehensively studied. The CSFB fermentation process can be clearly divided into early (0-25d) and later (25-60d) stages. A total of 364 genera and 71 volatiles were detected during the CSFB fermentation. FG starch and total acid had an extremely significant influence on prokaryotic community composition. Abstract: Fermented grain (FG), a complex and unique ecosystem, is the main microbial habitats, biochemical reaction system and direct source of flavor compounds for the Chinese strong-flavor Baijiu (CSFB) production. However, the dynamics of physicochemical properties, prokaryotic community and flavor compounds of FGs during the long-term fermentation process are still not completely clear. Here, the above topics on FGs in the actual production process were comprehensively studied by using a combination of physicochemical analysis, GC–MS detection and Illumina HiSeq sequencing methods. The whole fermentation process could be divided into two stages including early (0–25d) and the later stage (25–60d) based on the dynamics of FG physicochemical properties and the changes of prokaryotic community diversity. A total of 41phyla and 364 genera were detected, and 9 of them were dominant genera in FG complex ecosystem, including Lactobacillus, Pediococcus, Ochrobactrum, Bacillus etc. Among them, the dynamics of 29 top10 genera in FGs were mainly influenced by the starch and total acid, followed by NH4 + and ethanol, and 7 genera (hubs, e.g., Clostridium, Methanosaeta, Bacillus, etc.) of them may play important roles in FG ecosystem stability. A total of 71 volatiles including 33 esters, 14 alcohols, 9 fatty acids, 5 phenols, and 10 other compounds were detected in the FGs, and most of them formed in the early stage. Some important flavor substances (e.g., ethyl octanoate, 3-methylbutanol, hexanoate, etc.) increased in the later stage. Moreover, the formation of some flavor compound might require multiple microbes involved. For instance, ten of the top10 genera, including Lactobacillus, Clostridium, Methanosarcina, Sedimentibacter, Bacillus, etc., were significantly and positively correlated with four important esters. This study may help to clarify the complex correlations among prokaryotic community, physicochemical properties and flavors, allow the improvement of CSFB quality by using bioaugmentation and/or controlling environmental factors, and shed more light on the ecological rules guiding community assembly in FGs.