Microbial community changes during the mechanized production of light aromaXiaoqu baijiu

Abstract

Multi-microorganisms mixed fermentation is the main characteristic of Chinese baijiu brewing. In this study, plate culture and high-throughput sequencing were used to investigate the changes in microbial community during baijiu brewing. The results revealed that fungi accounted for the largest number of culturable microorganisms, followed by bacteria and molds. The diversity of bacteria and fungi first increased and then decreased, before increasing slightly at the late stage. Most microbial species came from the environment or raw materials, and the microbial community changed greatly during fermentation; thus, the dominant microorganisms in the starter might not be the dominant organisms during fermentation. The bacterial composition changed in a certain pattern, and the core microbes were lactic acid bacteria and Acetobacter pasteurianus. The composition of each genus was relatively uniform at the early stage, while Lactobacillus spp. were dominant at the late stage. Among them, Lactobacillus sp., which ranked first, had low initial abundance, before reaching 63.7% at the end. Four fungi, Saccharomyces cerevisiae, Wickerhamomyces anomalus, Aspergillus sp. and Rhizopus oryzae, were dominant, accounting for 74.6%-93.6% of the species present, among which the first two accounted for 50.3%-81.2%. This study provides a basis for the mechanized production of Xiaoqu baijiu.

Effects of ultra-long fermentation time on the microbial community and flavor components of light-flavor Xiaoqu Baijiu based on fermentation tanks

“…Wang and Xu ( 2019 ), and Huang et al ( 2020 ) revealed Bacillus and yeast were the most influential microorganisms in the early stage of fermentation, and lactic acid bacteria predominated in the late fermentation phase of light-flavor Baijiu . Hu et al ( 2021b ) used HTS to investigate the structure of the microbial community and indicated that the core microbes were Lactobacillus , A. pasteurianus , S. cerevisia e, W. anomalus , Aspergillus , and R. oryzae at the end of fermentation in the mechanized light-flavor Xiaoqu Baijiu production, which were basically in line with our results. But we newly found a fungus Condenascus that has not been reported in Baijiu , which formerly belonged to the classification of Thielavia (Wang et al 2019a ).…”

“…According to the production process, Jiuqu includes Daqu (Made with raw wheat, barley and/or peas), Xiaoqu (Made with rice or rice bran), and Fuqu (Made with bran) (Jin et al 2017 ). Light-flavor Xiaoqu Baijiu is produced by solid-state fermentation of sorghum with Xiaoqu (starter) containing various microbes and their complex interactions, which is a representative product made by Jing Brand Co., Ltd., one of the largest and most influential manufacturers of Xiaoqu Baijiu based on mechanized technology in China (Hu et al 2021b ). The quality evaluation standard of light-flavor Xiaoqu Baijiu mainly depends on sensory indexes and varieties and contents of core flavor compounds, which are associated with microbial metabolism during brewing process.…”

Chinese Baijiu: The Perfect Works of Microorganisms

“…Chinese Baijiu can be divided into 12 types according to their flavors. Among them, Maotai flavor, Luzhou flavor, light flavor, and rice flavor are the basic four flavor types, and other baijiu is the extension of these four flavors ( Zheng and Han, 2016 ; Xu et al, 2017b ; Hu Y. et al, 2021 ). The relationship between the 12 flavored baijiu types is shown in Figure 1 .…”

Study on microbial community of “green-covering” Tuqu and the effect of fortified autochthonous Monascus purpureus on the flavor components of light-aroma-type Baijiu

“…According to the practical production experiences, the TQ with red heart is often considered to be a reflection of high quality. In previous studies, a few yeasts, molds, and bacteria ( Hu et al, 2021a , b ; Tang et al, 2022 ), including Monascus were isolated from LATB. Then, Zhu et al (2014) reported that three Monascus ruber were isolated from red-heart Langjiu Daqu by plate separation.…”