This study investigated the aroma-active compounds and compared the differences of three different grades of sesame-flavor Baijiu by headspace solid-phase microextraction(HS-SPME)coupled with gas chromatography-olfact...This study investigated the aroma-active compounds and compared the differences of three different grades of sesame-flavor Baijiu by headspace solid-phase microextraction(HS-SPME)coupled with gas chromatography-olfactometry-mass spectrometry(GC-O-MS).A total of 54 aroma-active compounds were detected.Principal component analysis showed that JZ1,JZ2,and JZ3 were well separated from each other.JZ1 as the premium-grade Baijiu had the highest aroma intensities,concentrations.According to aroma intensities and concentrations,dimethyl trisulfide,butanoic acid,phenylacetaldehyde,2-furylmethanethiol,ethyl hexanoate,2,6-dimethylpyrazine,etc.could be potentially applied as volatile makers to distinguish the three different grades of sesame-flavor Baijiu as their significant difference(P<0.05)in three Baijiu samples.Roasted aroma had the significant difference(P<0.05)in three sample base on aroma profiles.Meanwhile,2-furylmethanethiol,2,6-dimethylpyrazine were related to the roasted aroma,they may be had a significant contribution to the differences of three different grades of sesame-flavor Baijiu.This study has provided a comprehensive understanding of the differences of three different grades of sesame-flavor Baijiu.展开更多
Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic fermentation.Such influences are imposed on yeast growth and fermentation performances inclu...Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic fermentation.Such influences are imposed on yeast growth and fermentation performances including the formation of secondary metabolites.Saccharomyces cerevisiae,the main yeast responsible for fermentation,has been studied extensively regarding nitrogen impacts.On the other hand,a similar study for non-Saccharomyces yeasts,whose contributions to winemaking have gradually been acknowledged,remains to be fully explored,with a few studies being reported.This review starts by discussing nitrogen impacts on non-Saccharomyces yeast growth and fermentation kinetics in different case scenarios,then proceeds to summarize the nitrogen preferences of individual yeast strains with regulation mechanisms elucidated by recent studies.Detailed discussions on the influences on the production of volatile compounds and proposed pathways therein are made,followed by future work suggested as the final section.In summarizing the nitrogen impacts on non-Saccharomyces yeasts throughout alcoholic fermentation,this review will be helpful in obtaining a more comprehensive view on these non-conventional wine yeasts in terms of nutrient requirements and corresponding volatile production.Research gaps will therefore be elucidated for future research.展开更多
High hydrostatic pressure has become a non-thermal alternative to thermal pasteurization in dairy product processing.In this study,we investigated the effects of the treatment of high hydrostatic pressure on the bacte...High hydrostatic pressure has become a non-thermal alternative to thermal pasteurization in dairy product processing.In this study,we investigated the effects of the treatment of high hydrostatic pressure on the bacterial composition in donkey milk using high-throughput sequencing technology and culture-dependent methods.Compared with the microbial composition in the untreated donkey milk,the relative percentage of Pseudomonas and Acinetobacter in donkey milk after high hydrostatic pressure was significantly decreased by 4.92%and 4.82%,respectively.Beta diversity analysis demonstrated that the treatment of high hydrostatic pressure affected the microbial composition in donkey milk significantly.The potential probiotic Enterococcus casseliflavus isolated from the untreated donkey milk has a good acidifying ability.This study revealed the effects of high hydrostatic pressure treatment on the microbial composition in donkey milk,exhibiting its practical industrial application and the potential use of biological resources in the future.展开更多
Structured light with more extended degrees of freedom(DoFs)and in higher dimensions is increasingly gaining traction and leading to breakthroughs such as super-resolution imaging,larger-capacity communication,and ult...Structured light with more extended degrees of freedom(DoFs)and in higher dimensions is increasingly gaining traction and leading to breakthroughs such as super-resolution imaging,larger-capacity communication,and ultraprecise optical trapping or tweezers.More DoFs for manipulating an object can access more maneuvers and radically increase maneuvering precision,which is of significance in biology and related microscopic detection.However,manipulating particles beyond three-dimensional(3D)spatial manipulation by using current all-optical tweezers technology remains difficult.To overcome this limitation,we theoretically and experimentally present six-dimensional(6D)structured optical tweezers based on tailoring structured light emulating rigid-body mechanics.Our method facilitates the evaluation of the methodology of rigid-body mechanics to synthesize six independent DoFs in a structured optical trapping system,akin to six-axis rigid-body manipulation,including surge,sway,heave,roll,pitch,and yaw.In contrast to previous 3D optical tweezers,our 6D structured optical tweezers significantly improved the flexibility of the path design of complex trajectories,thereby laying the foundation for next-generation functional optical manipulation,assembly,and micromechanics.展开更多
Objectives:Investigating the element profiles of Be,Al,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Se,Rb,Sr,Ag,Cd,Cs,La,Pr,Nd,Sm,Eu,Gd,Pb,Th,and U of Baijiu(Chinese liquors),and setting up their classification according to geographical...Objectives:Investigating the element profiles of Be,Al,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Se,Rb,Sr,Ag,Cd,Cs,La,Pr,Nd,Sm,Eu,Gd,Pb,Th,and U of Baijiu(Chinese liquors),and setting up their classification according to geographical origin.Materials and Methods:Twenty-eight Chinese liquors from Shandong,Guizhou,and Sichuan provinces were analyzed by inductively coupled plasma mass spectrometry with the aid of matrix matching,online internal calibration,and direct injection to determine the concentrations of the aforementioned 26 elements.Multivariate statistical analysis,based on the contents of elements in the liquors,was applied to differentiate the liquors from different origins.Results:Both the cluster analysis based on 11 elements and the discriminant analysis based on 5 elements can separate the liquors of Shandong Province from others.A leave-one-out cross test of the discriminant analysis data resulted in 100 per cent accuracy regarding the recognition ability and prediction ability for the liquors from Shandong Province,and an overall 75.0 per cent accuracy of its prediction for all the 28 total liquors.Limitations:The liquors of Guizhou and Sichuan provinces can not be differentiated successfully.Conclusions:The liquors produced in Shandong Province can be differentiated in a great extent from Guizhou and Sichuan provinces based on the multivariate statistical analysis of the concentration of elements in liquors,while those of Guizhou and Sichuan provinces can not be differentiated successfully due to their geographical adjacency.展开更多
基金supported by the National Natural Science Foundation of China (32172340)
文摘This study investigated the aroma-active compounds and compared the differences of three different grades of sesame-flavor Baijiu by headspace solid-phase microextraction(HS-SPME)coupled with gas chromatography-olfactometry-mass spectrometry(GC-O-MS).A total of 54 aroma-active compounds were detected.Principal component analysis showed that JZ1,JZ2,and JZ3 were well separated from each other.JZ1 as the premium-grade Baijiu had the highest aroma intensities,concentrations.According to aroma intensities and concentrations,dimethyl trisulfide,butanoic acid,phenylacetaldehyde,2-furylmethanethiol,ethyl hexanoate,2,6-dimethylpyrazine,etc.could be potentially applied as volatile makers to distinguish the three different grades of sesame-flavor Baijiu as their significant difference(P<0.05)in three Baijiu samples.Roasted aroma had the significant difference(P<0.05)in three sample base on aroma profiles.Meanwhile,2-furylmethanethiol,2,6-dimethylpyrazine were related to the roasted aroma,they may be had a significant contribution to the differences of three different grades of sesame-flavor Baijiu.This study has provided a comprehensive understanding of the differences of three different grades of sesame-flavor Baijiu.
基金supported by grants from the National Natural Science Foundation of China(32172340)。
文摘Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic fermentation.Such influences are imposed on yeast growth and fermentation performances including the formation of secondary metabolites.Saccharomyces cerevisiae,the main yeast responsible for fermentation,has been studied extensively regarding nitrogen impacts.On the other hand,a similar study for non-Saccharomyces yeasts,whose contributions to winemaking have gradually been acknowledged,remains to be fully explored,with a few studies being reported.This review starts by discussing nitrogen impacts on non-Saccharomyces yeast growth and fermentation kinetics in different case scenarios,then proceeds to summarize the nitrogen preferences of individual yeast strains with regulation mechanisms elucidated by recent studies.Detailed discussions on the influences on the production of volatile compounds and proposed pathways therein are made,followed by future work suggested as the final section.In summarizing the nitrogen impacts on non-Saccharomyces yeasts throughout alcoholic fermentation,this review will be helpful in obtaining a more comprehensive view on these non-conventional wine yeasts in terms of nutrient requirements and corresponding volatile production.Research gaps will therefore be elucidated for future research.
基金This work was supported by National Natural Science Foundation of China(Grant No.31901798)the Open Project Program of the Beijing Laboratory of Food Quality and Safety,Beijing Technology and Business University(FQS-202101).
文摘High hydrostatic pressure has become a non-thermal alternative to thermal pasteurization in dairy product processing.In this study,we investigated the effects of the treatment of high hydrostatic pressure on the bacterial composition in donkey milk using high-throughput sequencing technology and culture-dependent methods.Compared with the microbial composition in the untreated donkey milk,the relative percentage of Pseudomonas and Acinetobacter in donkey milk after high hydrostatic pressure was significantly decreased by 4.92%and 4.82%,respectively.Beta diversity analysis demonstrated that the treatment of high hydrostatic pressure affected the microbial composition in donkey milk significantly.The potential probiotic Enterococcus casseliflavus isolated from the untreated donkey milk has a good acidifying ability.This study revealed the effects of high hydrostatic pressure treatment on the microbial composition in donkey milk,exhibiting its practical industrial application and the potential use of biological resources in the future.
基金National Key Research and Development Program of China(2022YFA1404800,2019YFA0705000)National Natural Science Foundation of China(12274116,11974102,12192254,92250304,11974218)+2 种基金Key Scientific Research Projects of Institutions of Higher Learning of Henan Province Education Department(21zx002)Natural Science Foundation of Henan Province(232300421019)State Key Laboratory of Transient Optics and Photonics(SKLST202216)。
文摘Structured light with more extended degrees of freedom(DoFs)and in higher dimensions is increasingly gaining traction and leading to breakthroughs such as super-resolution imaging,larger-capacity communication,and ultraprecise optical trapping or tweezers.More DoFs for manipulating an object can access more maneuvers and radically increase maneuvering precision,which is of significance in biology and related microscopic detection.However,manipulating particles beyond three-dimensional(3D)spatial manipulation by using current all-optical tweezers technology remains difficult.To overcome this limitation,we theoretically and experimentally present six-dimensional(6D)structured optical tweezers based on tailoring structured light emulating rigid-body mechanics.Our method facilitates the evaluation of the methodology of rigid-body mechanics to synthesize six independent DoFs in a structured optical trapping system,akin to six-axis rigid-body manipulation,including surge,sway,heave,roll,pitch,and yaw.In contrast to previous 3D optical tweezers,our 6D structured optical tweezers significantly improved the flexibility of the path design of complex trajectories,thereby laying the foundation for next-generation functional optical manipulation,assembly,and micromechanics.
基金the National Key R&D Program of China(2016YFD0400500)the National Natural Science Foundation of China(31601556)Beijing Natural Science Foundation Program and Scientific Research Key Program of Beijing Municipal Commission of Education(KZ201410011015).
文摘Objectives:Investigating the element profiles of Be,Al,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Se,Rb,Sr,Ag,Cd,Cs,La,Pr,Nd,Sm,Eu,Gd,Pb,Th,and U of Baijiu(Chinese liquors),and setting up their classification according to geographical origin.Materials and Methods:Twenty-eight Chinese liquors from Shandong,Guizhou,and Sichuan provinces were analyzed by inductively coupled plasma mass spectrometry with the aid of matrix matching,online internal calibration,and direct injection to determine the concentrations of the aforementioned 26 elements.Multivariate statistical analysis,based on the contents of elements in the liquors,was applied to differentiate the liquors from different origins.Results:Both the cluster analysis based on 11 elements and the discriminant analysis based on 5 elements can separate the liquors of Shandong Province from others.A leave-one-out cross test of the discriminant analysis data resulted in 100 per cent accuracy regarding the recognition ability and prediction ability for the liquors from Shandong Province,and an overall 75.0 per cent accuracy of its prediction for all the 28 total liquors.Limitations:The liquors of Guizhou and Sichuan provinces can not be differentiated successfully.Conclusions:The liquors produced in Shandong Province can be differentiated in a great extent from Guizhou and Sichuan provinces based on the multivariate statistical analysis of the concentration of elements in liquors,while those of Guizhou and Sichuan provinces can not be differentiated successfully due to their geographical adjacency.