The influence of stacking fermentation on pit fermentation is multifaceted in the Maotai flavor Baijiu(MFB).However,the influence and contribution degree of stacking fermentation on pit fermentation have not been full...The influence of stacking fermentation on pit fermentation is multifaceted in the Maotai flavor Baijiu(MFB).However,the influence and contribution degree of stacking fermentation on pit fermentation have not been fully clarified,and microbial community(MC)assembly modes in the heap and pit have not been clearly defined.Based on the analysis of the microbial community structure of stacking and pit fermentations,it was found that 60.82%of the bacteria and 49.07% of the fungi in the pit originated from the heap.Additionally,all the dominant microorganisms in the pit were also derived from the heap.Moreover,the bacterial contribution degree of the heap was generally higher than that of the fungi,and their contribution degrees to the microorganisms in the pit reached the highest at 3rd and 4th rounds,which were 84.81%and 71.88%,respectively.Furthermore,the volatile compounds of heap fermented grains had a relatively high contribution degree to the accumulation of alcohols,fatty acids and aromatic compounds in the pit.Meanwhile,environmental factors drove Thermomonas and Byssochlamys to construct MC in the heap,while drove Wickerhamomyces and Sphingomonas for constructing the MC of the pit.Finally,the MC assembly of the heap and pit both took the random assembly process as the predominant one.The bacterial community of the heap and pit were mainly assembled by the non-dominant process(64.43%,52.61%),while the fungal community of the heap and pit fermented grains were mainly assembled by the non-dominant process(47.96%)and the dispersal limitation assembly(43.48%),respectively.This work clearly clarified the influence and contribution degree of stacking fermentation on pit fermentation,and revealed the MC assembly modes of heap and pit fermented grains,offering significant practical implications for optimizing the fermentation quality of MFB.展开更多
The fermentation of sauce-flavor Baijiu requires high-temperature Daqu as the starter,which is classified into three types:white,yellow,and black.Recent studies highlighted the variability of the microbiota and metab-...The fermentation of sauce-flavor Baijiu requires high-temperature Daqu as the starter,which is classified into three types:white,yellow,and black.Recent studies highlighted the variability of the microbiota and metab-olome profiles of these three types of Daqu,however,what functions they precisely provide in the sauce-flavor Baijiu brewing process remains unclear.In this study,white,yellow,and black Daqu in five different proportions were utilized as starters in field-scale Baijiu fermentation,with the control group lacking Daqu inoculation.Fermented grains inoculated with 100%white Daqu(47.7℃)had the highest temperature during stacking fermentation,while 100%black Daqu and control groups were lower than 45℃.Lactic acid(12.6-22.0 mg/g)was the most abundant organic acid,followed by acetic acid(0.7-5.0 mg/g).qPCR analysis revealed that bac-terial biomass decreased during fermentation,while fungal biomass increased.A comparison with the control revealed that Daqu contributed high-temperature resistant microorganisms to the stacking fermentation process,primarily Kroppenstedtia,Virgibacillus,Byssochlamys,Thermoascus,and Thermomyces.Meanwhile,stacking fermentation promoted the enrichment of Acetobacter,Kazachstania,and Leiothecium.Mantel test and co-occurrence network analysis revealed that utilizing different fermentation starters could vary the biotic and abiotic factors that drive microbial community succession.We investigated the flavor of Baijiu further,and found that fermentation with white Daqu enhanced the accumulation of ethyl acetate,isoamyl alcohol,and isobutanol,whereas black Daqu increased the accumulation of ethyl lactate,lactic acid,and furfural.This study contributes to the rational usage of different types of Daqu in the manufacturing of Baijiu.展开更多
Stacked fermentation is the process of utilizing microorganisms in the environment and further enriching their population in Jiupei.However,the composition of microbial communities in the different layers of Jiupei an...Stacked fermentation is the process of utilizing microorganisms in the environment and further enriching their population in Jiupei.However,the composition of microbial communities in the different layers of Jiupei and their relationship with sensory quality requires more clarity.This study analyzed the microbial composition of the different layers of Jiupei in the fourth round of stacked fermentation using high-throughput sequencing technology.Physicochemical properties and sensory qualities were measured;the correlation between the observed microorganisms and sensory quality was further analyzed.The results showed that there were significant differences in acidity,moisture,starch,reducing sugar,and protein content across the different layers of the Jiupei(P<0.05).The flavor substances in the entire Jiupei dump primarily included organic sulfides,terpenes,and ethanol,and umami was the most dominant taste indicator.Significant differences in microbial community structure were observed across the layers of the Jiupei,with the main bacterial genera being Thermoactinomyces(63.95%),and Bacillus(11.77%).Meanwhile,the main fungal genera identified were Pichia(28.37%),Saccharomyces(24.42%),and Byssochlamys(17.01%).The correlation between the microorganisms and the sensory indexes in Jiupei was found to be significant(P<0.05);the presence of the bacterial genera Bacillus and Thermoactinomyces and the fungal genera Saccharomyces,Byssochlamys,and Zygosaccharomyces was found to be related to the sensory quality of Jiupei.This study provides insights into the role of microorganisms in the fourth round of liquor fermentation and provides a theoretical reference for the subsequent optimization of sauce-flavor liquor quality.展开更多
基金supported by National Natural Science Foundation of China(32460269)Guizhou Provincial Basic Research Program(Natural Science)key project(QianKeHeJiChu-ZD[2025]018)+3 种基金Moutai Institute&Guizhou Guiding distillery cooperation research and development project(XYNJ20240374)Guizhou Provincial Science and Technology Projects of China([2020]1Y144)the Fund of Zunyi Technology and Big data Bureau,Moutai institute Joint Science and Technology Research and Development Project(ZunShiKeHe HZ Zi[2023]108&[2023]374)Research Foundation for Scientific Scholars of Moutai Institute(mygccrc[2022]034,mygccrc[2022]133,mygccrc[2022]017,mygccrc[2024]001).
文摘The influence of stacking fermentation on pit fermentation is multifaceted in the Maotai flavor Baijiu(MFB).However,the influence and contribution degree of stacking fermentation on pit fermentation have not been fully clarified,and microbial community(MC)assembly modes in the heap and pit have not been clearly defined.Based on the analysis of the microbial community structure of stacking and pit fermentations,it was found that 60.82%of the bacteria and 49.07% of the fungi in the pit originated from the heap.Additionally,all the dominant microorganisms in the pit were also derived from the heap.Moreover,the bacterial contribution degree of the heap was generally higher than that of the fungi,and their contribution degrees to the microorganisms in the pit reached the highest at 3rd and 4th rounds,which were 84.81%and 71.88%,respectively.Furthermore,the volatile compounds of heap fermented grains had a relatively high contribution degree to the accumulation of alcohols,fatty acids and aromatic compounds in the pit.Meanwhile,environmental factors drove Thermomonas and Byssochlamys to construct MC in the heap,while drove Wickerhamomyces and Sphingomonas for constructing the MC of the pit.Finally,the MC assembly of the heap and pit both took the random assembly process as the predominant one.The bacterial community of the heap and pit were mainly assembled by the non-dominant process(64.43%,52.61%),while the fungal community of the heap and pit fermented grains were mainly assembled by the non-dominant process(47.96%)and the dispersal limitation assembly(43.48%),respectively.This work clearly clarified the influence and contribution degree of stacking fermentation on pit fermentation,and revealed the MC assembly modes of heap and pit fermented grains,offering significant practical implications for optimizing the fermentation quality of MFB.
基金supported by the Research Foundation for Scientific Scholars of Moutai Institute(mygccrc[2022]012).
文摘The fermentation of sauce-flavor Baijiu requires high-temperature Daqu as the starter,which is classified into three types:white,yellow,and black.Recent studies highlighted the variability of the microbiota and metab-olome profiles of these three types of Daqu,however,what functions they precisely provide in the sauce-flavor Baijiu brewing process remains unclear.In this study,white,yellow,and black Daqu in five different proportions were utilized as starters in field-scale Baijiu fermentation,with the control group lacking Daqu inoculation.Fermented grains inoculated with 100%white Daqu(47.7℃)had the highest temperature during stacking fermentation,while 100%black Daqu and control groups were lower than 45℃.Lactic acid(12.6-22.0 mg/g)was the most abundant organic acid,followed by acetic acid(0.7-5.0 mg/g).qPCR analysis revealed that bac-terial biomass decreased during fermentation,while fungal biomass increased.A comparison with the control revealed that Daqu contributed high-temperature resistant microorganisms to the stacking fermentation process,primarily Kroppenstedtia,Virgibacillus,Byssochlamys,Thermoascus,and Thermomyces.Meanwhile,stacking fermentation promoted the enrichment of Acetobacter,Kazachstania,and Leiothecium.Mantel test and co-occurrence network analysis revealed that utilizing different fermentation starters could vary the biotic and abiotic factors that drive microbial community succession.We investigated the flavor of Baijiu further,and found that fermentation with white Daqu enhanced the accumulation of ethyl acetate,isoamyl alcohol,and isobutanol,whereas black Daqu increased the accumulation of ethyl lactate,lactic acid,and furfural.This study contributes to the rational usage of different types of Daqu in the manufacturing of Baijiu.
基金supported by the Hubei Provincial Natural Science Foundation Joint Fund for Innovation and Development Project(2023AFD049)Science Foundation for Cultivation Fund for Teachers’Scientific Research Ability:“Technological Innovation Team”(2020kypytd009).
文摘Stacked fermentation is the process of utilizing microorganisms in the environment and further enriching their population in Jiupei.However,the composition of microbial communities in the different layers of Jiupei and their relationship with sensory quality requires more clarity.This study analyzed the microbial composition of the different layers of Jiupei in the fourth round of stacked fermentation using high-throughput sequencing technology.Physicochemical properties and sensory qualities were measured;the correlation between the observed microorganisms and sensory quality was further analyzed.The results showed that there were significant differences in acidity,moisture,starch,reducing sugar,and protein content across the different layers of the Jiupei(P<0.05).The flavor substances in the entire Jiupei dump primarily included organic sulfides,terpenes,and ethanol,and umami was the most dominant taste indicator.Significant differences in microbial community structure were observed across the layers of the Jiupei,with the main bacterial genera being Thermoactinomyces(63.95%),and Bacillus(11.77%).Meanwhile,the main fungal genera identified were Pichia(28.37%),Saccharomyces(24.42%),and Byssochlamys(17.01%).The correlation between the microorganisms and the sensory indexes in Jiupei was found to be significant(P<0.05);the presence of the bacterial genera Bacillus and Thermoactinomyces and the fungal genera Saccharomyces,Byssochlamys,and Zygosaccharomyces was found to be related to the sensory quality of Jiupei.This study provides insights into the role of microorganisms in the fourth round of liquor fermentation and provides a theoretical reference for the subsequent optimization of sauce-flavor liquor quality.
