Diversity and formation mechanism of the microflora in strong flavor Baijiu Baobaoqu
ZHANG Qian1, HAN Baolin1,2, LI Zijian1, XIE Jun1,2, YU Dong3, ZOU Yongfang3, GUO Huixiang3, WEN Jing3, ZHANG Lingling1, LUO Huibo1,2*, HUANG Dan1,2*
1(College of Bioengineering,Sichuan University of Science & Engineering,Zigong 643000,China) 2(Liquor Making Biotechnology and Application Key Laboratory of Sichuan Province,Yibin 644000,China) 3(Shede Spirits Co.Ltd.,Suining 629209,China)
Abstract: The structural succession rule of the microflora of Qupi (representing the surface of Baobaoqu, marked as QP below) and Quxin (representing the interior of Baobaoqu, marked as QX below) in the process of the spontaneous solid-state fermentation (SSF) of Baobaoqu was studied. The correlation between the microflora structure and the physicochemical factors of QP and QX, the diversity of microflora and the formation mechanism of diversity endowed by the unique structure of Baobaoqu were also analyzed. The pH, total acid, temperature, and moisture of QP and QX in the process of SSF were measured, the microflora structure in QP and QX was studied by high-throughput sequencing method, and the difference of microflora between QP and QX was analyzed by linear discriminant analysis effect size (LEfSe). Redundancy analysis, mantel test analysis, and Pearson correlation analysis were used to analyze the correlation between the physicochemical factors and the microflora of Baobaoqu. The results showed that there were significant differences in the bacterial and fungal communities between these two groups. Lactobacillus, Weissella, Rhizopus, Rhizomucor, Pichia, Aspergillus had higher abundances in QP. The abundance of Thermoascus, Pseudomonadales, Rhizobiales, Saccharomycetales, and Sporidiobolaleswas higher in QX. Meanwhile, it was also found that pH, total acid, temperature, and moisture were important factors affecting the microbial composition of QP and QX. The results revealed the characteristics and differences of microflora structure in QP and QX during the Baobaoqu SSF process, which might be helpful to the analysis of the formation mechanism of microbial diversity in Baobaoqu.
 DU H, WANG X S, ZHANG Y H, et al.Exploring the impacts of raw materials and environments on the microbiota in Chinese Daqu starter[J].International Journal of Food Microbiology, 2019, 297:32-40.  赵东, 杨蓉.白酒酿造微生物培养技术研究[J].酿酒, 2014, 41(6):21-25. ZHAO D, YANG R.The research on the techniques of cultivation liquor-making microbes[J].Liquor Making, 2014, 41(6):21-25.  WANG Z M, WANG C T, SHEN C H, et al.Microbiota stratification and succession of amylase-producing Bacillus in traditional Chinese Jiuqu (fermentation starters)[J].Journal of the Science of Food and Agriculture, 2020, 100(8):3 544-3 553.  明红梅, 陈晓旭, 刘清斌, 等.泸型大曲曲表与曲心理化生化特性的对比研究[J].湖北农业科学, 2015, 54(6):1 445-1 447;1 451. MING H M, CHEN X X, LIU Q B, et al.Comparative studies on physicochemical and biochemical indicators between surface and inner about Luzhou Laojiao Daqu[J].Hubei Agricultural Sciences, 2015, 54(6):1 445-1 447;1 451.  李家民, 王海英, 张文学, 等.用DGGE方法初步解析浓香型大曲微生物群落结构[J].酿酒科技, 2012(11):32-35. LI J M, WANG H Y, ZHANG W X, et al.Preliminary analysis of microbial communities structure in Luzhou-flavor Daqu by DGGE[J].Liquor-Making Science & Technology, 2012(11):32-35.  姚万春, 唐玉明, 任道群, 等.泸州老窖国窖曲曲坯层次间微生物差异研究[J].酿酒, 2005,32(5):35-37. YAO W C, TANG Y M, REN D Q, et al.Study on the differences of microbes in the different layers of Guojiao Daqu[J].Liquor Making, 2005,32(5):35-37.  ZOU W, ZHAO C Q, LUO H B.Diversity and function of microbial community in Chinese strong-flavor Baijiu ecosystem:A review[J].Frontiers in Microbiology, 2018, 9:671.  JIN Y, LI D Y, AI M, et al.Correlation between volatile profiles and microbial communities:A metabonomic approach to study Jiang-flavor liquor Daqu[J].Food Research International, 2019, 121:422-432.  CHEN Y R, LI K M, LIU T, et al.Analysis of difference in microbial community and physicochemical indices between surface and central parts of Chinese special-flavor baijiu Daqu[J].Frontiers in Microbiology, 2021.DOI:10.3389/fmicb.2020.592421.  中国轻工业联合会. QB/T 4257—2011 酿酒大曲通用分析方法[S].北京:中华人民共和国工业和信息化部, 2011. China National Light Industry Council.QB/T 4257—2011 General analysis method for brewing Daqu[S].Beijing:Ministry of Industry and Information Technology of the People′s Republic of China, 2011.  夏玙, 罗惠波, 周平, 等.不同处理方式的大曲真菌群落差异分析[J].食品科学, 2018, 39(22):166-172. XIA Y, LUO H B, ZHOU P, et al.Comparison of fungal communities in Daqu with different treatments[J].Food Science, 2018, 39(22):166-172.  CALLAHAN B J, MCMURDIE P J, ROSEN M J, et al.DADA2:High-resolution sample inference from Illumina amplicon data[J].Nature Methods, 2016, 13(7):581-583.  LI P, LIN W F, LIU X, et al.Environmental factors affecting microbiota dynamics during traditional solid-state fermentation of Chinese Daqu starter[J].Frontiers in Microbiology, 2016, 7:1 237.  GUAN T W, LIN Y J, CHEN K B, et al.Physicochemical factors affecting microbiota dynamics during traditional solid-state fermentation of Chinese strong-flavor Baijiu[J].Frontiers in Microbiology, 2020, 11:2 090.  CHEN B, WU Q, XU Y.Filamentous fungal diversity and community structure associated with the solid state fermentation of Chinese Maotai-flavor liquor[J].International Journal of Food Microbiology, 2014, 179:80-84.  SOCCOL C R, COSTA E S F D, LETTI L A J, et al.Recent developments and innovations in solid state fermentation[J].Biotechnology Research and Innovation, 2017, 1(1):52-71.  TANG J, TANG X X, TANG M, et al.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[J].BioMed Research International, 2017.DOI:10.1155/2017/6271358.  ZHAO Y Y, YANG Y Z, HE F, et al.Pseudomonas xionganensis sp.nov., isolated from Baiyangdian Lake in Xiong′an New Area[J].International Journal of Systematic and Evolutionary Microbiology, 2020, 70(12):6 052-6 059.  HAAS D, DéFAGO G.Biological control of soil-borne pathogens by fluorescent Pseudomonads[J].Nature Reviews Microbiology, 2005, 3(4):307-319.  WANG X S, DU H, ZHANG Y, et al.Environmental microbiota drives microbial succession and metabolic profiles during Chinese liquor fermentation[J].Applied and Environmental Microbiology, 2018, 84(4).DOI:10.1128/AEM.02369-17.  DENG L, MAO X, LIU D, et al.Comparative analysis of physicochemical properties and microbial composition in high-temperature Daqu with different colors[J].Frontiers in Microbiology, 2020, 11:588 117.  TAN Y W, ZHONG H P, ZHAO D, et al.Succession rate of microbial community causes flavor difference in strong-aroma Baijiu making process[J].International Journal of Food Microbiology, 2019, 311:108 350.  LI K M, CHEN Y R, LIU T, et al.Analysis of spatial distribution of bacterial community associated with accumulation of volatile compounds in Jiupei during the brewing of special-flavor liquor[J].LWT, 2020, 130:109620.  王柏文, 吴群, 徐岩, 等.中国白酒酒曲微生物组研究进展及趋势[J].微生物学通报,2021,48(5):1 737-1 746. WANG B W, WU Q, XU Y, et al.Recent advances and perspectives in study of microbiome in Chinese Jiuqu starter[J].Microbiology China,2021,48(5):1 737-1 746.  XIAO C, LU Z M, ZHANG X J, et al.Bio-heat is a key environmental driver shaping the microbial community of medium-temperature Daqu[J].Applied and Environmental Microbiology, 2017, 83(23).DOI:10.1128/AEM.01550-17.