High-temperature Daqu is a crucial starter for Chinese Baijiu,yet how wheat substrate characteristics and MFH additives jointly influence microbial assembly and flavor metabolism remains unclear.Here,two wheat varieti...High-temperature Daqu is a crucial starter for Chinese Baijiu,yet how wheat substrate characteristics and MFH additives jointly influence microbial assembly and flavor metabolism remains unclear.Here,two wheat varieties with distinct physicochemical properties(WA and WC)were used to construct three Daqu systems:WA with MFH(QA),WA without MFH(QB),and WC with MFH(QC).We systematically tracked their physicochemical,mi-crobial,and flavor dynamics.The two wheat varieties differed significantly in moisture,reducing sugars,total starch,amylose,amylopectin,fat,and protein contents,driving distinct trajectories in Daqu physicochemical and enzymatic activities.Volatile profiling revealed distinct flavor profiles,with QC showing stronger accumulation of pyrazines and phenolic compounds.Amplicon sequencing indicated that substrate properties primarily drove microbial succession,whereas MFH addition more strongly influenced fungal community variation.Ecological modeling revealed that bacterial assembly in QC involved a greater stochastic contribution,whereas QA and QB were governed by deterministic environmental filtering.Integrated structural modeling and functional predic-tion analyses further suggested that these ecological divergences were associated with distinct flavor-related metabolic patterns,particularly phenylalanine-,pyrazine-,and ester-related pathways.Collectively,wheat substrate properties were identified as the primary ecological filter in Daqu fermentation,with MFH showing substrate-dependent modulatory effects.This study provides a theoretical basis for microbial regulation and flavor optimization in high-temperature Daqu production.展开更多
基金support obtained from The National Key Research and Development Program of China(2022YFD2101401).
文摘High-temperature Daqu is a crucial starter for Chinese Baijiu,yet how wheat substrate characteristics and MFH additives jointly influence microbial assembly and flavor metabolism remains unclear.Here,two wheat varieties with distinct physicochemical properties(WA and WC)were used to construct three Daqu systems:WA with MFH(QA),WA without MFH(QB),and WC with MFH(QC).We systematically tracked their physicochemical,mi-crobial,and flavor dynamics.The two wheat varieties differed significantly in moisture,reducing sugars,total starch,amylose,amylopectin,fat,and protein contents,driving distinct trajectories in Daqu physicochemical and enzymatic activities.Volatile profiling revealed distinct flavor profiles,with QC showing stronger accumulation of pyrazines and phenolic compounds.Amplicon sequencing indicated that substrate properties primarily drove microbial succession,whereas MFH addition more strongly influenced fungal community variation.Ecological modeling revealed that bacterial assembly in QC involved a greater stochastic contribution,whereas QA and QB were governed by deterministic environmental filtering.Integrated structural modeling and functional predic-tion analyses further suggested that these ecological divergences were associated with distinct flavor-related metabolic patterns,particularly phenylalanine-,pyrazine-,and ester-related pathways.Collectively,wheat substrate properties were identified as the primary ecological filter in Daqu fermentation,with MFH showing substrate-dependent modulatory effects.This study provides a theoretical basis for microbial regulation and flavor optimization in high-temperature Daqu production.
