This study aimed to investigate microbial succession and metabolic dynamics during the traditional fermentation of Hongqu aged vinegar,and explore the core functional microbes closely related to the formation of flavo...This study aimed to investigate microbial succession and metabolic dynamics during the traditional fermentation of Hongqu aged vinegar,and explore the core functional microbes closely related to the formation of flavor components.Microbiome analysis demonstrated that Lactobacillus,Acetobacter,Bacillus,Enterobacter,Lactococcus,Leuconostoc and Weissella were the predominant bacterial genera,while Aspergillus piperis,Aspergillus oryzae,Monascus purpureus,Candida athensensis,C.xylopsoci,Penicillium ochrosalmoneum and Simplicillium aogashimaense were the predominant fungal species.Correlation analysis revealed that Acetobacter was positively correlated with the production of tetramethylpyrazine,acetoin and acetic acid,Lactococcus showed positive correlation with the production of 2-nonanone,2-heptanone,ethyl caprylate,ethyl caprate,1-hexanol,1-octanol and 1-octen-3-ol,C.xylopsoci and C.rugosa were positively associated with the production of diethyl malonate,2,3-butanediyl diacetate,acetoin,benzaldehyde and tetramethylpyrazine.Correspondingly,non-volatile metabolites were also detected through ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry.A variety of amino acids and functional dipeptides were identified during the traditional brewing of Hongqu aged vinegar.Correlation analysis revealed that Lactobacillus was significantly associated with DL-lactate,indolelactic acid,D-(+)-3-phenyllactic acid,pimelic acid,pregabalin and 3-aminobutanoic acid.This study is useful for understanding flavor formation mechanism and developing effective strategies for the suitable strains selection to improve the flavor quality of Hongqu aged vinegar.展开更多
[Objectives]This study was conducted to explore the dynamic changes of volatile flavor compounds in prepared pork during storage at different low-temperature conditions.[Methods]Prepared pork was stored at 4,-4 and-18...[Objectives]This study was conducted to explore the dynamic changes of volatile flavor compounds in prepared pork during storage at different low-temperature conditions.[Methods]Prepared pork was stored at 4,-4 and-18℃.The volatile flavor compounds of prepared pork were determined by solid-phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS)at days 0,7,14,21 and 28,and relative odor activity value(OAV),principal component analysis(PCA)and cluster analysis(CA)were combined to analyze changes in volatile flavor compounds of prepared pork during storage.[Results]The total number of volatile flavor compounds gradually decreased with the prolongation of the storage period,and OAV analysis identified 22 key flavor compounds(OAV≥1).The results of PCA and CA showed that 2-methyl-1-butanol,1-octen-3-ol,linalool,cineole,hexanal and nonanal were the main key flavor components,and the degree of flavor degradation was low under both superchilling and freezing conditions.After 28 days of storage,the alcohol content in the chilling group was significantly higher than other two groups,and the overall content of volatile flavor compounds was also significantly higher than other two groups,indicating that the-4℃chilling storage was more favorable for maintaining the overall flavor of prepared pork.[Conclusions]This study provides a theoretical basis for finding a better storage method for prepared meat products.展开更多
Pea(Pisum sativum L.)is an important source of plant proteins.However,the use of pea flour as a food ingredient is greatly limited due to its strong beany flavor.In this work,we investigated the effects of Lactobacill...Pea(Pisum sativum L.)is an important source of plant proteins.However,the use of pea flour as a food ingredient is greatly limited due to its strong beany flavor.In this work,we investigated the effects of Lactobacillus rhamnosus L08(L.rhamnosus L08)fermentation on the physicochemical characteristics,amino acids composition and volatile flavor compounds of pea flour.We found that L.rhamnosus L08 had the probiotic potential of utilizing pea flour as fermentation substrate.L.rhamnosus L08 fermentation significantly increased the content of most amino acids,and total amino acid content increased from 222.18 mg/g at 0 h to 262.35 mg/g at 6 h.A total of 44 volatile compounds were identified in pea flour.L.rhamnosus L08 fermentation increased the variety of acids and esters,while reduced the unpleasant flavor such as nonanal,decanal,octanal,1-hexanol and 2-ethyl-1-hexanol.The emulsifying stability and foam stability of pea flour were slightly enhanced during fermentation.Our results illustrate that lactic acid bacteria fermentation is a promising approach to eliminate undesirable aroma of pea flour.Moreover,this study provides theoretical support for the application of peas as high-quality protein source.展开更多
The co-fermentation of summer-autumn tea with Aspergillus niger and Eurotium cristatum effectively reduces bitterness and astringency,enhances flavor and quality,and increases market appeal and economic value.This stu...The co-fermentation of summer-autumn tea with Aspergillus niger and Eurotium cristatum effectively reduces bitterness and astringency,enhances flavor and quality,and increases market appeal and economic value.This study investigated the dynamic changes in metabolites,flavor characteristics and quality indicators of summerautumn tea during fermentation.Using headspace solid-phase microextraction gas chromatography(HS-SPMEGC-MS),96 key metabolites were identified,significantly enhancing the tea’s aroma and flavor.On the fourth day of fermentation,the content of ester catechins(EGCG,ECG)decreased by 79.44% and 79.57%,respectively,while non-ester catechins(EGC,C,EC)increased by 175.47%,228.18%,and 138.73%,respectively.Additionally,the gallic acid content increased by 755.58%,along with rises in free amino acids and soluble sugars.Sensory evaluation focused on taste,soup color,and aroma,resulting in a total score of 80.67.The intensity of astringency,bitterness,and sourness in the tea infusion gradually decreased,while sweetness,umami,and aroma intensified.These findings underscore the significant role of the synergistic action of the three strains in developing the unique flavor profile of summer-autumn tea during fermentation.This research lays the foundation for quality control and resource development in the processing of summer-autumn tea.展开更多
Fermented chili pepper paste is a popular condiment in many Chinese cuisines.This study elucidates the fermentation mechanisms of chili paste at varying salt concentrations,providing foundation for the development of ...Fermented chili pepper paste is a popular condiment in many Chinese cuisines.This study elucidates the fermentation mechanisms of chili paste at varying salt concentrations,providing foundation for the development of low-salt fermented chili paste.We monitored the physicochemical parameters,microbial succession,and flavor and biogenic amines over a six-month fermentation period at salt concentrations of 8%,10%,12%,14%,17%,and 20%.Results indicated that higher salt concentrations increased bacterial diversity and richness,while the optimal salt levels for fungal diversity and richness were 10%and 12%.Lower salt concentrations facilitated the rapid accumulation of total acidity,amino nitrogen,free amino acids,and organic acids.However,excessively low salt concentration led to the undesirable accumulation of biogenic amines.Chili paste fermented with higher salinity(12%,14%,and 17%)exhibited a greater diversity and higher content of volatile compounds,thereby enhancing the sauce aroma.The use of multi-layer sealed bags effectively prevented spoilage,demonstrating excellent sealing properties,simplicity,and applicability.Among the tested salt concentrations,chili paste fermented with 12%salt demonstrated the best balance of flavor profile,microbial composition,and sensory quality,making it optimal for producing low-salt fermented chili paste with desirable flavor and safety profiles.展开更多
To compare the difference of non-volatile taste-active flavor components of different chicken breeds,four Chinese native yellow feather broilers including Langshan chicken,Chongren chicken,Luyuan chicken and Wenchang ...To compare the difference of non-volatile taste-active flavor components of different chicken breeds,four Chinese native yellow feather broilers including Langshan chicken,Chongren chicken,Luyuan chicken and Wenchang chicken were used in the experiment.The contents of free amino acids,5’-nucleotides and minerals were determined by standard method,and then five principal components were extracted from the multi-index system based on the principal component analysis(PCA).Combined with the Mahalanobis distance analysis method and sensory evaluation results,the advantages and characteristics of each chicken breed were evaluated.The results showed that different kinds of chicken had their own advantages in different evaluation dimensions.The Equivalent umami concentration(ECU)of Wenchang chicken,which had the highest content of amino acids,was 12 g monosodium glutamate(MSG)/100 g,indicating the umami taste of it was very intense.The indexes of Langshan chicken were relatively uniform,with slightly higher mineral content,its overall Mahalanobis distance score was more similar to the"best standard".According to the Mahalanobis distance score,although the difference in amino acid content among each species was the largest,the overall score was more affected by the content of minerals and nucleotides,and there was interaction between each nutrient,which had an impact on the overall Mahalanobis distance score.The sensory evaluation results indicated that Wenchang chicken was the most superior among the taste of the four varieties investigated.Finally,taste compounds affecting the difference of chicken varieties were analyzed by partial least squares regression(PLS),resulting in order of mineral(Ca^(2+) ,Mg^(2+) ,PO_(4)^(3−))>nucleotide(AMP,IMP)>amino acid.This could provide a theoretical basis for quantitative oriented flavor processing and consumer choice of chicken.展开更多
Zhenjiang aromatic vinegar(ZAV),known for its distinctive flavors,is produced through traditional solid-state fermentation involving multiple strains.The development of functional microbial communities during repeated...Zhenjiang aromatic vinegar(ZAV),known for its distinctive flavors,is produced through traditional solid-state fermentation involving multiple strains.The development of functional microbial communities during repeated batch acetic acid fermentation(AAF)is crucial for flavor formation in ZAV.Hence,investigating the two pivotal factors,namely flavor synthesis and microbial strains,within the vinegar ecosystem is essential for the vinegar industry to modulate the metabolic function of vinegar microbiota,monitor the fermentation process,and maintain the desired flavor quality of the final product.This study aimed to explore the ecological interactions of Bacillus within the vinegar Pei and examine the correlation between the Bacillus community and the characteristic aroma components of ZAV.The findings demonstrated that the dynamic of Bacillus community was drove by environmental factors represented by temperature and acidity,together with the interactions between microorganisms.Moreover,Bacillus exhibited a significant positive correlation with 34 volatile flavor components,including 7 alcohols,1 acid,20 esters,3 aldehydes,2 ketones,and 1 phenol.The characteristic aroma components strongly associated with Bacillus were identified as lactic acid,six ethyl esters,namely ethyl acetate,benzeneacetaldehyde,and 3-methylbutyraldehyde.Overall,this study revealed the crucial role of Bacillus in maintaining fermentation system stability and facilitating flavor synthesis.The detailed insights provided here contributed to a better understanding of the fermentation mechanisms underlying ZAV.展开更多
基金funded by Outstanding Talent of“Qishan Scholar”of Fuzhou University of China(GXRC21049)the Open Project Program of the Beijing Laboratory of Food Quality and Safety,Beijing Technology and Business University(BTBU)(FQS-201802,FQS-202008).
文摘This study aimed to investigate microbial succession and metabolic dynamics during the traditional fermentation of Hongqu aged vinegar,and explore the core functional microbes closely related to the formation of flavor components.Microbiome analysis demonstrated that Lactobacillus,Acetobacter,Bacillus,Enterobacter,Lactococcus,Leuconostoc and Weissella were the predominant bacterial genera,while Aspergillus piperis,Aspergillus oryzae,Monascus purpureus,Candida athensensis,C.xylopsoci,Penicillium ochrosalmoneum and Simplicillium aogashimaense were the predominant fungal species.Correlation analysis revealed that Acetobacter was positively correlated with the production of tetramethylpyrazine,acetoin and acetic acid,Lactococcus showed positive correlation with the production of 2-nonanone,2-heptanone,ethyl caprylate,ethyl caprate,1-hexanol,1-octanol and 1-octen-3-ol,C.xylopsoci and C.rugosa were positively associated with the production of diethyl malonate,2,3-butanediyl diacetate,acetoin,benzaldehyde and tetramethylpyrazine.Correspondingly,non-volatile metabolites were also detected through ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry.A variety of amino acids and functional dipeptides were identified during the traditional brewing of Hongqu aged vinegar.Correlation analysis revealed that Lactobacillus was significantly associated with DL-lactate,indolelactic acid,D-(+)-3-phenyllactic acid,pimelic acid,pregabalin and 3-aminobutanoic acid.This study is useful for understanding flavor formation mechanism and developing effective strategies for the suitable strains selection to improve the flavor quality of Hongqu aged vinegar.
基金Supported by Science and Technology Achievement Transformation Program of Sichuan Province(2023ZHCG0079)Research and Application of Key Techniques for Industrialization of Frozen Prepared Meat Dishes(GCZX22-35)Sichuan Pig Innovation Team of National Agricultural Industry Technology System(scsztd-2024-08-07).
文摘[Objectives]This study was conducted to explore the dynamic changes of volatile flavor compounds in prepared pork during storage at different low-temperature conditions.[Methods]Prepared pork was stored at 4,-4 and-18℃.The volatile flavor compounds of prepared pork were determined by solid-phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS)at days 0,7,14,21 and 28,and relative odor activity value(OAV),principal component analysis(PCA)and cluster analysis(CA)were combined to analyze changes in volatile flavor compounds of prepared pork during storage.[Results]The total number of volatile flavor compounds gradually decreased with the prolongation of the storage period,and OAV analysis identified 22 key flavor compounds(OAV≥1).The results of PCA and CA showed that 2-methyl-1-butanol,1-octen-3-ol,linalool,cineole,hexanal and nonanal were the main key flavor components,and the degree of flavor degradation was low under both superchilling and freezing conditions.After 28 days of storage,the alcohol content in the chilling group was significantly higher than other two groups,and the overall content of volatile flavor compounds was also significantly higher than other two groups,indicating that the-4℃chilling storage was more favorable for maintaining the overall flavor of prepared pork.[Conclusions]This study provides a theoretical basis for finding a better storage method for prepared meat products.
基金This study was supported by the Distinguished Young Foundation of Heilongjiang Province of China(JQ2020C006)Natural Science Foundation of Heilongjiang Province of China(Grant No.C2018022)+1 种基金Academic Backbone Plan of Northeast Agricultural University(Grant No.18XG27)“Characteristic Probiotics and New Fermented Food”Team in Northeast Agricultural University.
文摘Pea(Pisum sativum L.)is an important source of plant proteins.However,the use of pea flour as a food ingredient is greatly limited due to its strong beany flavor.In this work,we investigated the effects of Lactobacillus rhamnosus L08(L.rhamnosus L08)fermentation on the physicochemical characteristics,amino acids composition and volatile flavor compounds of pea flour.We found that L.rhamnosus L08 had the probiotic potential of utilizing pea flour as fermentation substrate.L.rhamnosus L08 fermentation significantly increased the content of most amino acids,and total amino acid content increased from 222.18 mg/g at 0 h to 262.35 mg/g at 6 h.A total of 44 volatile compounds were identified in pea flour.L.rhamnosus L08 fermentation increased the variety of acids and esters,while reduced the unpleasant flavor such as nonanal,decanal,octanal,1-hexanol and 2-ethyl-1-hexanol.The emulsifying stability and foam stability of pea flour were slightly enhanced during fermentation.Our results illustrate that lactic acid bacteria fermentation is a promising approach to eliminate undesirable aroma of pea flour.Moreover,this study provides theoretical support for the application of peas as high-quality protein source.
基金supported by the National Natural Science Foundation of China(32302107)Open Fund of the Guangdong Provincial Key Laboratory of Utilization and Conservation of Food and Medicinal Re-sources in Northern Region(FMR2023005Z)Youth Innovative Talent Project of General Universities in Guangdong Province(2023KQNCX010).
文摘The co-fermentation of summer-autumn tea with Aspergillus niger and Eurotium cristatum effectively reduces bitterness and astringency,enhances flavor and quality,and increases market appeal and economic value.This study investigated the dynamic changes in metabolites,flavor characteristics and quality indicators of summerautumn tea during fermentation.Using headspace solid-phase microextraction gas chromatography(HS-SPMEGC-MS),96 key metabolites were identified,significantly enhancing the tea’s aroma and flavor.On the fourth day of fermentation,the content of ester catechins(EGCG,ECG)decreased by 79.44% and 79.57%,respectively,while non-ester catechins(EGC,C,EC)increased by 175.47%,228.18%,and 138.73%,respectively.Additionally,the gallic acid content increased by 755.58%,along with rises in free amino acids and soluble sugars.Sensory evaluation focused on taste,soup color,and aroma,resulting in a total score of 80.67.The intensity of astringency,bitterness,and sourness in the tea infusion gradually decreased,while sweetness,umami,and aroma intensified.These findings underscore the significant role of the synergistic action of the three strains in developing the unique flavor profile of summer-autumn tea during fermentation.This research lays the foundation for quality control and resource development in the processing of summer-autumn tea.
基金supported by National Modern Agricultural Industrial Technology System Sichuan Vegetable Innovation Team SCCXTD-2024Solid-state Brewing Technology Innovation Center of Sichuan.
文摘Fermented chili pepper paste is a popular condiment in many Chinese cuisines.This study elucidates the fermentation mechanisms of chili paste at varying salt concentrations,providing foundation for the development of low-salt fermented chili paste.We monitored the physicochemical parameters,microbial succession,and flavor and biogenic amines over a six-month fermentation period at salt concentrations of 8%,10%,12%,14%,17%,and 20%.Results indicated that higher salt concentrations increased bacterial diversity and richness,while the optimal salt levels for fungal diversity and richness were 10%and 12%.Lower salt concentrations facilitated the rapid accumulation of total acidity,amino nitrogen,free amino acids,and organic acids.However,excessively low salt concentration led to the undesirable accumulation of biogenic amines.Chili paste fermented with higher salinity(12%,14%,and 17%)exhibited a greater diversity and higher content of volatile compounds,thereby enhancing the sauce aroma.The use of multi-layer sealed bags effectively prevented spoilage,demonstrating excellent sealing properties,simplicity,and applicability.Among the tested salt concentrations,chili paste fermented with 12%salt demonstrated the best balance of flavor profile,microbial composition,and sensory quality,making it optimal for producing low-salt fermented chili paste with desirable flavor and safety profiles.
基金supported financially by Molecular Sensory Study on the Mechanism of Aroma Formation in Tibetan Chicken Processing(KYYZ2022001)the China Agriculture Research System of MOF and MARA(CARS-41).
文摘To compare the difference of non-volatile taste-active flavor components of different chicken breeds,four Chinese native yellow feather broilers including Langshan chicken,Chongren chicken,Luyuan chicken and Wenchang chicken were used in the experiment.The contents of free amino acids,5’-nucleotides and minerals were determined by standard method,and then five principal components were extracted from the multi-index system based on the principal component analysis(PCA).Combined with the Mahalanobis distance analysis method and sensory evaluation results,the advantages and characteristics of each chicken breed were evaluated.The results showed that different kinds of chicken had their own advantages in different evaluation dimensions.The Equivalent umami concentration(ECU)of Wenchang chicken,which had the highest content of amino acids,was 12 g monosodium glutamate(MSG)/100 g,indicating the umami taste of it was very intense.The indexes of Langshan chicken were relatively uniform,with slightly higher mineral content,its overall Mahalanobis distance score was more similar to the"best standard".According to the Mahalanobis distance score,although the difference in amino acid content among each species was the largest,the overall score was more affected by the content of minerals and nucleotides,and there was interaction between each nutrient,which had an impact on the overall Mahalanobis distance score.The sensory evaluation results indicated that Wenchang chicken was the most superior among the taste of the four varieties investigated.Finally,taste compounds affecting the difference of chicken varieties were analyzed by partial least squares regression(PLS),resulting in order of mineral(Ca^(2+) ,Mg^(2+) ,PO_(4)^(3−))>nucleotide(AMP,IMP)>amino acid.This could provide a theoretical basis for quantitative oriented flavor processing and consumer choice of chicken.
基金the National Natural Science Foundation of China(No.32072202)the Graduate Research and Innovation Projects of Jiangsu Province(No.1182162203)for financial support.
文摘Zhenjiang aromatic vinegar(ZAV),known for its distinctive flavors,is produced through traditional solid-state fermentation involving multiple strains.The development of functional microbial communities during repeated batch acetic acid fermentation(AAF)is crucial for flavor formation in ZAV.Hence,investigating the two pivotal factors,namely flavor synthesis and microbial strains,within the vinegar ecosystem is essential for the vinegar industry to modulate the metabolic function of vinegar microbiota,monitor the fermentation process,and maintain the desired flavor quality of the final product.This study aimed to explore the ecological interactions of Bacillus within the vinegar Pei and examine the correlation between the Bacillus community and the characteristic aroma components of ZAV.The findings demonstrated that the dynamic of Bacillus community was drove by environmental factors represented by temperature and acidity,together with the interactions between microorganisms.Moreover,Bacillus exhibited a significant positive correlation with 34 volatile flavor components,including 7 alcohols,1 acid,20 esters,3 aldehydes,2 ketones,and 1 phenol.The characteristic aroma components strongly associated with Bacillus were identified as lactic acid,six ethyl esters,namely ethyl acetate,benzeneacetaldehyde,and 3-methylbutyraldehyde.Overall,this study revealed the crucial role of Bacillus in maintaining fermentation system stability and facilitating flavor synthesis.The detailed insights provided here contributed to a better understanding of the fermentation mechanisms underlying ZAV.
