Soybean is one of the important crops in China. Soymilk, a traditional neutral plant-based protein drink, is rich in high quality proteins. Although soybean milk is rich in nutrients, its marketing among consumers, es...Soybean is one of the important crops in China. Soymilk, a traditional neutral plant-based protein drink, is rich in high quality proteins. Although soybean milk is rich in nutrients, its marketing among consumers, especially those in Western countries who are used to peaceful flavor, has been limited due to the adverse flavor impact brought by its special composition. In recent years, with the increasing attention to the nutritional value of soymilk, the flavor of soymilk has become a popular research object for scholars at home and abroad. The flavor components of soymilk are mainly volatile small molecular compounds produced by enzymatic reactions catalyzed by lipoxygenase(LOX). After formation, they interact with protein macromolecules to form the overall flavor of soymilk. At present, there are many methods to control the off-odor of soymilk at home and abroad, including physical heating methods, chemical methods, biological enzymatic digestion methods, mask methods, and a variety of breeding methods. These methods effectively reduce the off-odor of soymilk, but all of them have shortcomings. Currently, the sensory characteristics of the beany odor in soymilk are evaluated mainly by traditional human sensory scoring along with the assistance of modern instrument analysis of volatile flavor substances using headspace solid phase microextraction(SPME) gas chromatography coupled with-mass spectrometry(GC-MS). This paper summarized the research results of volatile flavor substances in soymilk in recent years and the sensory evaluation methods of soymilk at home and abroad, and looked forward to the future development direction, hoping to provide some theoretical bases and reference detection methods for solving the problem of soymilk flavor in the future.展开更多
Fatty acids and volatile substances in hybrid pork(Duroc×Landrace×Yorkshire;DLY)and four indigenous pork(Guangdong small-ear spotted;hill black;Beijing black,BB;and Qingyu)in raw,cooked,and reheated states w...Fatty acids and volatile substances in hybrid pork(Duroc×Landrace×Yorkshire;DLY)and four indigenous pork(Guangdong small-ear spotted;hill black;Beijing black,BB;and Qingyu)in raw,cooked,and reheated states were explored.The objectives were to determine odor differences between DLY and indigenous pork and the difference in changes after heating and reheating and to clarify the reasons for these changes.Results revealed that C18:1 and C20:4 fatty acids are the key to distinguishing DLY pork from indigenous pork.After cooking,the greatest decrease was observed in the proportion of polyunsaturated fatty acids in pork,and after reheating,monounsaturated fatty acids were detected,except in the BB pork.The substances that accounted for the dif-ference between DLY and indigenous pork were 2,3-octadione,hexanal,1-octen-3-ol,2-nonanone(after heating),and(Z)-2-nonenal(after reheating).Reheating reduced the content of nonanal,2,3-octandione,hexanal,and(E,E)-2,4-decadienal,resulting in the deterioration of the aroma.In the DLY pork,the dramatic increase in the(Z)-2-nonenal content may be the key factor.Principal component analysis identified that the difference in aroma between DLY and indigenous pork increased after reheating,but hierarchical cluster analysis showed that regardless of treatment,flavor difference was smaller between DLY and indigenous pork than among indigenous pigs.The analysis results show that differences in fatty acid content and oxidation path in unsaturated fatty acids were the reasons for the difference in aroma and the deterioration of flavor after reheating.展开更多
Chili fermentation is one of the most important processes in the production of Pixian Douban(PXDB),which determines the flavor and product quality of PXDB.However,the maturity of fermented chili mainly depends on empi...Chili fermentation is one of the most important processes in the production of Pixian Douban(PXDB),which determines the flavor and product quality of PXDB.However,the maturity of fermented chili mainly depends on empirical judgment,which can not satisfy the need for standardized production of PXDB.Therefore,this study aimed to investigate volatile and non-volatile substances during the maturation process and to find markers related to the maturity of fermented chili.Two-dimensional gas chromatography-mass spectrometry(GC×GC-MS)combined with multivariate statistical analysis and relative odor activity values(ROAV)analysis revealed that 2-methoxy-3-isobutyl pyrazine,linalool,3-(methylthio)propionaldehyde,myrcene,and decanal(ROAV≥1,VIP>1,P<0.05)were regarded as potentially active aromatic markers for differentiating fermentation time.Additionally,ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLCQTOF-MS)combined with multivariate statistical analysis revealed that 25 compounds could serve as differentiated non-volatile compounds.The correlation of maturity-related physicochemical indicators with volatile and nonvolatile compounds revealed that four volatile compounds(2-methoxy-3-isobutylpyrazine,linalool,myrcene,and decanal)along with seven non-volatile compounds could serve as markers for evaluating the maturity of fermented chili.This study is expected to establish a standard for the determination of the maturity the fermented chili and lay the foundation for intelligent production of PXDB.展开更多
Exogenous additions and storage time affect the nutritional and sensory properties of fermented products.This study investigated the effect of natural cyclodextrin on the nutritional indicators and overall quality of ...Exogenous additions and storage time affect the nutritional and sensory properties of fermented products.This study investigated the effect of natural cyclodextrin on the nutritional indicators and overall quality of Saccharomyces cerevisiae and Lactiplantibacillus plantarum sequentially fermented apple juice,and further studied the quality changes during the shelf life.Results showed that the cyclodextrin significantly affected the quality of apple juice during sequential fermentation and storage,especiallyβ-cyclodextrin increased the total polyphenols and flavonoids of apple juice after sequential fermentation reached 0.67 g/L and 0.42 g/L;DPPH and ABTS radical scavenging rate increased to 76.33%and 77.55%;increased the organic acids and monomeric phenols.β-CD has a positive effect on the generation and protection of higher alcohols and esters,especially ethyl acetate and heptyl acetate.Compared with other groups,the addition ofβ-CD before fermentation showed superior color retention in terms of lightness(L^(*))and yellow(b^(*))index under 4℃ and 25℃.Additionally,the aroma and sensory qualities of the product were improved and preserved.Therefore,the addition of cyclodextrin before fermentation not only improved the nutritional quality and antioxidant activity of fermented juice,retained and improved the aroma and color,but also stabilized the comprehensive quality during storage.展开更多
Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South Chin...Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South China. This study explored the effect of different diets on the volatile flavor and nutritional ingredients of O. vulgaris. Four diets were tested in four groups: Group A(fish(Scomberomorus niphonius)), Group B(crab(Helice tridens tientsinensis Rathbun)), Group C(clam(Mactra veneriformis)), and Group D(squid(Loligo japonica)). Octopus muscles were sampled after 36 days of feeding, and volatile flavor substances(VFSs), fatty acids(FAs), and amino acids(AAs) were detected. Results showed that the VFSs, FAs, and AAs of octopus in the four groups were obviously different. The sum of volatile ketones and aldehydes was higher in Group B than in the other groups, which could present much more flavors. All groups were abundant in unsaturated FAs, including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA). In terms of content and variety, the FAs in Group B were more beneficial to human health than those in the other groups. The content of each AA in Group B was basically higher than those in the other groups and was significantly higher than that in Group D(P < 0.05). Comparing the VFSs, FAs, and AAs in samples fed with four kinds of diets, the results indicate that using crab to feed O. vulgaris can achieve better effects on volatile flavor and nutritional ingredients.展开更多
An unusual form of localized corrsion in copper tubes was detected early in service and in leakage tests after manufacturing.The morphology of this corrosion is similar to that of an ant's nest when viewed in cros...An unusual form of localized corrsion in copper tubes was detected early in service and in leakage tests after manufacturing.The morphology of this corrosion is similar to that of an ant's nest when viewed in cross section. The corrosion mechanisms, cases ofant's nest corrosion, and preventive measures are presented.展开更多
Simultaneous distillation-extractor was used for extracting the volatile substances in Llex Kudincha.26 volatile components were identified by gas chromatography mass spectrometry (GC-MS)method.The identified compound...Simultaneous distillation-extractor was used for extracting the volatile substances in Llex Kudincha.26 volatile components were identified by gas chromatography mass spectrometry (GC-MS)method.The identified compounds are 94.83 % of the total volatile substances.展开更多
[Objective] The aim was to provide theoretical basis for the exploitation and utilization of Trifolium. [Method] This paper introduced the main active ingredients,pharmacological effects and applications of Trifolium,...[Objective] The aim was to provide theoretical basis for the exploitation and utilization of Trifolium. [Method] This paper introduced the main active ingredients,pharmacological effects and applications of Trifolium, and looked into research focus and direction in the future. [ Result] The main active ingredient of Trifolium is leaves protein concentration, isoflavones, chlorogenic acid and volatile substance. [ Conclusion] Trifolium resources in our country is abundant, which has been thought to be the most potential health food and new medical resources. It becomes research hotspot in the field of health food, biological medicine and related fields with its biological functions and pharmacological effects. We should strength- en the exploitation and utilization of Trifolium active ingredients apart from its forage function.展开更多
In lunar science,volatiles are defined as chemical elements and unstable compounds,evaporating,sublimating,or flowing in other ways at low temperature.At moderate temperature,volatiles transfers its flowing elements f...In lunar science,volatiles are defined as chemical elements and unstable compounds,evaporating,sublimating,or flowing in other ways at low temperature.At moderate temperature,volatiles transfers its flowing elements from solid materials to coexisting gas phases.Such substances include S,Cu,Zn,As,Se,Ag,Cd,In,Te,Hg,Ti,Pb,Bi,and halogens(F,C L,Br,and I).These volatile substances are mainly added by small impactors,so they should be uniformly deposited in lunar regolith.In the permanently shaded regions(PSRs)of the lunar polar region,the extremely low temperature may allow the solar activity record to be kept longer.When the lunar soil is heated,it will release volatile elements in the form of gas,especially the particles injected into the lunar soil by the solar wind.In deeper lunar soil,it means that these particles were implanted in different periods of solar evolution.The study of regolith in polar PSRs may help to solve this problem,because it has not been widely heated and therefore may not be subjected to postimplantation modification.The research on volatiles detection in lunar polar region can help us confirm the content and distribution of water ice in the permanent shadow region of the lunar polar region,and the composition,distribution,source,transport and loss mechanism of other volatiles in this region,as well as the relationship between lunar soil in the polar region and the ancient solar wind environment,and the environment and mineral resources in the region.Chandrayaan-3 provided important assistance to the conceptualization of this project.At the end of the article,we discussed the lunar orbit.展开更多
The presence of a fishy odor has emerged as a significant obstacle in the processing and commercialization of tilapia.In light of this,the present study employed ultrasonic-assisted enzyme deodorization to address thi...The presence of a fishy odor has emerged as a significant obstacle in the processing and commercialization of tilapia.In light of this,the present study employed ultrasonic-assisted enzyme deodorization to address this issue.The deodorization effects were evaluated from multiple perspectives,including chemical indexes(amino acid nitrogen content,trimethylamine content,and thiobarbituric acid value),physical indexes(texture),and sensory scores.Through the application of response surface methodology,an ultrasound-complex enzyme deodorization(UED)technology was ultimately optimized.The UED process resulted in a 56%reduction in trimethylamine content while also enhancing the taste,odor,and texture of the fish,thereby demonstrating its ability to significantly improve overall quality.Additionally,headspace solid-phase microextraction gas chromatographymass spectrometry(HS-SPME-GC/MS)and gas chromatography-ion mobility spectrometry(GC-IMS)were utilized to comprehensively analyze the impact of UED on flavor and elucidate its deodorization mechanism.Notably,UED samples exhibited reduced levels of components associated with undesirable fishy flavors such as hexanal,nonanal,1-octen-3-ol,and ethyl propanoate while experiencing an increase in components such as benzaldehyde,cis-Jasmone,and butyl lactate that contribute pleasant fruity and floral aromas.Overall,this study has developed an efficient convenient method for both deodorizing tilapia enhancing its aroma,making valuable contributions towards improving overall flavor profile tilapia products.展开更多
Coffee is currently the second largest commodity on the world market today,and there is great concern about the quality of the beans exported from producer countries to Europe and USA.Practices such as using blends of...Coffee is currently the second largest commodity on the world market today,and there is great concern about the quality of the beans exported from producer countries to Europe and USA.Practices such as using blends of different species and adding low-cost raw materials,such as chicory,corn,and soybean,impair the sensory and functional characteristics of the drink made from roasted and ground coffee beans.There is a need to adopt more efficient analytical methods than the microscopy technique currently used.The first chromatographic method used to determine fraud was reported in 1958.This method used paper chromatography to differentiate between coffee and chicory based on the free reducing sugars.As of the 1980s,different methods involving high-performance liquid chromatography and gas chromatography were developed in order to demonstrate geographic authenticity,distinction between species,occurrence of adulteration,and the presence of defective beans by determining the monosaccharides,oligosaccharides,tocopherols,fatty acids,volatiles,diterpenes,sterols,and phenolic substances,among others.As far as the authors know,there are no papers published in the literature that have compiled such an extensive set of information about these chromatographic methods as here.Over the last 2 years,there has been a trend to develop analytical methods for ultra-performance liquid chromatography coupled with tandem mass spectrometry to confirm fraud in coffee,due to high sensitivity and selectivity.展开更多
A six-week feeding trial was carried out to determine the feasibility of cottonseed oil(CSO)as a viable substitute for fish oil(FO)in the commercial diet of swimming crabs.Ninety healthy swimming crabs(initial body we...A six-week feeding trial was carried out to determine the feasibility of cottonseed oil(CSO)as a viable substitute for fish oil(FO)in the commercial diet of swimming crabs.Ninety healthy swimming crabs(initial body weight 34.28±0.59 g)were randomly assigned to 90 plastic baskets.Three isonitrogenous and isolipidic diets(450 g/kg protein and 120 g/kg lipid)were formulated replacing FO with CSO at 0%,50%and 100%(CSO-0,CSO-50,and CSO-100),respectively.Each diet was randomly allocated to three replicates,each consisting of 10 crabs.Results indicated that crabs fed with CSO-100 diet had the lowest the percent weight gain(PWG),specific growth rate(SGR)and survival among all treatments(P<0.05).Albumin(ALB),glucose(GLU),triglyceride(TAG),total cholesterol(T-CHO),low-density lipoprotein cholesterol(LDL-C),non-esterified fatty acid(NEFA)contents and alkaline phosphatase(ALP),alanine amino transferase(ALT)activity in hemolymph were significantly affected by dietary substitution of FO with CSO(P<0.05).The contents of total saturated fatty acids(SFA),total mono-unsaturated fatty acids(MUFA)and total long-chain polyunsaturated fatty acids(LC-PUFA)in the hepatopancreas and muscle were negatively correlated with the substitution level,whereas total n-6 polyunsaturated fatty acids(n-6 PUFA)and linoleic acid(18:2n-6)contents increased significantly with increasing levels of dietary substitution of FO with CSO(P<0.05).Dietary substitution of FO with CSO resulted in changes in the composition of volatile substances in muscle,with 16 volatile substances in muscle significantly affected(P<0.05).The relative expression of genes related to lipid synthesis such as fatty acid synthase(fas),acetyl-CoA carboxylase(acc)and glycerol-3-phosphate acyltransferase 1(gpat1)in the hepatopancreas were significantly up-regulated in the CSO-50 group compared to other treatment groups(P<0.05).The relative expression of fatty acid anabolism-related genes fatty acyl desaturase 2(fads2)and elongase 4(elovl4)were significantly down-regulated with the increase of dietary substitution of FO with CSO(P<0.05).In conclusion,50%substitution with CSO had no negative effects on growth performance,promoted lipid synthesis and metabolism,facilitated lipid accumulation.However,complete substitution of FO with CSO inhibited fatty acid synthesis and metabolism,resulting in a lower tissue LC-PUFA content and an altered composition of muscle volatiles.展开更多
We evaluated the changes in volatile and nonvolatile flavor substances after fermented milk was fermented by Lacticaseibacillus rhamnosus WH.FH-19 using Headspace Solid Phase Microextraction-Gas Chromatography-Mass Sp...We evaluated the changes in volatile and nonvolatile flavor substances after fermented milk was fermented by Lacticaseibacillus rhamnosus WH.FH-19 using Headspace Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry(HS-SPME-GC-MS)and High-Performance Liquid Chromatography-Mass Spectrometry(HPLC-MS).The results have shown that the addition of L.rhamnosus WH.FH-19 can increase the contents of acetoin and 2-nonanone which can give fermented milk cream and cheese flavor,and significantly enrich amino acid meta-bolism and carbon metabolism.The fermentation of L.rhamnosus WH.FH-19 increased the contents of L-glu-tamic acid,taurine,stachyose,erythritol,L-rhamnose,retinol,pantothenic acid and 19 oligopeptides in fermented milk,and endowed fermented milk with good flavor,quality and antioxidant capacity.The results presented that L.rhamnosus WH.FH-19 can increase the content of flavor substances,promote the metabolism of amino acids and carbohydrates in fermented milk,and produce more antioxidant metabolites,which had the potential as a starter of fermented milk.展开更多
The undesirable odor of crab meatballs was evident after boiling and cooling,high-voltage electrostatic field(HVEF),lysozyme and yeast extract(LY),and the combination(LYH)were all applied to pre-deodorize crab meatbal...The undesirable odor of crab meatballs was evident after boiling and cooling,high-voltage electrostatic field(HVEF),lysozyme and yeast extract(LY),and the combination(LYH)were all applied to pre-deodorize crab meatballs to estimate the effect in view of odor,pH,fat oxidation and protein oxidation.None of the tert-butylamine(1.58±0.14 ng/g),(E,E)-2,4-Dodecadienal(18.52±0.12 ng/g),1-Octen-3-ol(13.51±0.22 ng/g)and nonanal(681.55±0.24 ng/g)in the control were detected in LYH group,while nonanal in HVEF and LY groups was reduced by 86.07%and 42.60%,respectively.Thirteen volatile substances with variable importance plot≥1 contributed prominently to the odor of crab meatballs depended on partial least squares discrimination analysis.Protein oxidation of the pretreated crab meatballs was alleviated,as well as thiobarbituric acid reactive substances(TBARS)and lipoxygenase(LOX)activity,with the best inhibitory effect of LYH being 40.10%and 62.80%on the respective effects.The correlation analysis derived that fishy substances were significantly positively correlated with TBARS and pH.LYH was the optimal pre-deodorization,which involved promoting glycolysis and lactic acid bacteria colonization in the liquid medium,and inhibiting fat oxidation by affecting enzyme activity in HVEF.展开更多
The primary objective of this study was to investigate the effect of fermentation with Lactobacillus acidophilus 6074 on the nutrient transformation and quality characteristics of jujube juice.The screened L.acidophil...The primary objective of this study was to investigate the effect of fermentation with Lactobacillus acidophilus 6074 on the nutrient transformation and quality characteristics of jujube juice.The screened L.acidophilus 6074 with acid and bile salt resistance was used to ferment jujube juice,and the sensory properties and nutrient biotransformation of the fermented product were comprehensively evaluated.The results showed that the acid and bile salt resistance of L.acidophilus 6074 were 94.06%and 84.56%,respectively,and the viable counts after fermentation reached 8.75 lg CFU/mL.Total sugar and polysaccharide content decreased after fermentation,while total flavonoids,cAMP and triterpenoic acid increased significantly,as did organic acids and free amino acids(p<0.05).Moreover,the L.acidophilus 6074 fermentation reduced the molecular weight of the main polysaccharide component from 746,111.957 Da to 573,809.851 Da,and its microstructure changed.A total of 62 volatile compounds were identified in fermented jujube juice,among which acids were the highest,followed by esters.Particularly,L.acidophilus 6074 fermentation increased the content of phenylethyl acetate and lactic acid,generating new substances clopenthixol and phenylethyl alcohol of jujube juice.Sensory evaluation indicated that L.acidophilus 6074 fermentation improved the coloration of jujube juice and increased the overall acceptability of the fermented product.This study will provide theoretical basis and technical support for the industrial production of probiotic fermentation jujube juice related products.展开更多
基金Supported by the Youth Fund Project of the National Natural Science Foundation of China(32001570)the Post-doctorate Program Funding in Heilongjiang Province(LBH-Z19118)the Academic Backbone'Project of Northeast Agricultural University(20XG11)。
文摘Soybean is one of the important crops in China. Soymilk, a traditional neutral plant-based protein drink, is rich in high quality proteins. Although soybean milk is rich in nutrients, its marketing among consumers, especially those in Western countries who are used to peaceful flavor, has been limited due to the adverse flavor impact brought by its special composition. In recent years, with the increasing attention to the nutritional value of soymilk, the flavor of soymilk has become a popular research object for scholars at home and abroad. The flavor components of soymilk are mainly volatile small molecular compounds produced by enzymatic reactions catalyzed by lipoxygenase(LOX). After formation, they interact with protein macromolecules to form the overall flavor of soymilk. At present, there are many methods to control the off-odor of soymilk at home and abroad, including physical heating methods, chemical methods, biological enzymatic digestion methods, mask methods, and a variety of breeding methods. These methods effectively reduce the off-odor of soymilk, but all of them have shortcomings. Currently, the sensory characteristics of the beany odor in soymilk are evaluated mainly by traditional human sensory scoring along with the assistance of modern instrument analysis of volatile flavor substances using headspace solid phase microextraction(SPME) gas chromatography coupled with-mass spectrometry(GC-MS). This paper summarized the research results of volatile flavor substances in soymilk in recent years and the sensory evaluation methods of soymilk at home and abroad, and looked forward to the future development direction, hoping to provide some theoretical bases and reference detection methods for solving the problem of soymilk flavor in the future.
基金funded by the Sichuan Science and Technology Pro-gram(Project No.2021YFN0037)National Key R&D Program of China(Project No.2021YFD2100804).
文摘Fatty acids and volatile substances in hybrid pork(Duroc×Landrace×Yorkshire;DLY)and four indigenous pork(Guangdong small-ear spotted;hill black;Beijing black,BB;and Qingyu)in raw,cooked,and reheated states were explored.The objectives were to determine odor differences between DLY and indigenous pork and the difference in changes after heating and reheating and to clarify the reasons for these changes.Results revealed that C18:1 and C20:4 fatty acids are the key to distinguishing DLY pork from indigenous pork.After cooking,the greatest decrease was observed in the proportion of polyunsaturated fatty acids in pork,and after reheating,monounsaturated fatty acids were detected,except in the BB pork.The substances that accounted for the dif-ference between DLY and indigenous pork were 2,3-octadione,hexanal,1-octen-3-ol,2-nonanone(after heating),and(Z)-2-nonenal(after reheating).Reheating reduced the content of nonanal,2,3-octandione,hexanal,and(E,E)-2,4-decadienal,resulting in the deterioration of the aroma.In the DLY pork,the dramatic increase in the(Z)-2-nonenal content may be the key factor.Principal component analysis identified that the difference in aroma between DLY and indigenous pork increased after reheating,but hierarchical cluster analysis showed that regardless of treatment,flavor difference was smaller between DLY and indigenous pork than among indigenous pigs.The analysis results show that differences in fatty acid content and oxidation path in unsaturated fatty acids were the reasons for the difference in aroma and the deterioration of flavor after reheating.
基金supported by the Sichuan Provincial Department of Science and Technology(2024ZHCG0086)the Chongqing Science and Technology Commission(cstc2021jscx-cylhX0014).
文摘Chili fermentation is one of the most important processes in the production of Pixian Douban(PXDB),which determines the flavor and product quality of PXDB.However,the maturity of fermented chili mainly depends on empirical judgment,which can not satisfy the need for standardized production of PXDB.Therefore,this study aimed to investigate volatile and non-volatile substances during the maturation process and to find markers related to the maturity of fermented chili.Two-dimensional gas chromatography-mass spectrometry(GC×GC-MS)combined with multivariate statistical analysis and relative odor activity values(ROAV)analysis revealed that 2-methoxy-3-isobutyl pyrazine,linalool,3-(methylthio)propionaldehyde,myrcene,and decanal(ROAV≥1,VIP>1,P<0.05)were regarded as potentially active aromatic markers for differentiating fermentation time.Additionally,ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLCQTOF-MS)combined with multivariate statistical analysis revealed that 25 compounds could serve as differentiated non-volatile compounds.The correlation of maturity-related physicochemical indicators with volatile and nonvolatile compounds revealed that four volatile compounds(2-methoxy-3-isobutylpyrazine,linalool,myrcene,and decanal)along with seven non-volatile compounds could serve as markers for evaluating the maturity of fermented chili.This study is expected to establish a standard for the determination of the maturity the fermented chili and lay the foundation for intelligent production of PXDB.
基金supported by grants from The National Key R&D Program of China(2023YFF130510403)。
文摘Exogenous additions and storage time affect the nutritional and sensory properties of fermented products.This study investigated the effect of natural cyclodextrin on the nutritional indicators and overall quality of Saccharomyces cerevisiae and Lactiplantibacillus plantarum sequentially fermented apple juice,and further studied the quality changes during the shelf life.Results showed that the cyclodextrin significantly affected the quality of apple juice during sequential fermentation and storage,especiallyβ-cyclodextrin increased the total polyphenols and flavonoids of apple juice after sequential fermentation reached 0.67 g/L and 0.42 g/L;DPPH and ABTS radical scavenging rate increased to 76.33%and 77.55%;increased the organic acids and monomeric phenols.β-CD has a positive effect on the generation and protection of higher alcohols and esters,especially ethyl acetate and heptyl acetate.Compared with other groups,the addition ofβ-CD before fermentation showed superior color retention in terms of lightness(L^(*))and yellow(b^(*))index under 4℃ and 25℃.Additionally,the aroma and sensory qualities of the product were improved and preserved.Therefore,the addition of cyclodextrin before fermentation not only improved the nutritional quality and antioxidant activity of fermented juice,retained and improved the aroma and color,but also stabilized the comprehensive quality during storage.
基金supported by the earmarked fund for the Modern Agro-Industry Technology Research System (No. CARS-49)the Natural Science Foundation of Shan-dong Province (No. ZR2018BC052)+1 种基金the Entrepreneurship and Innovation Talents programme of Jiangsu Province of China (2020–2023)the Huaguo Mountain Talent Pro-gramme of Lianyungang City Jiangsu Province (2019–2022)。
文摘Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South China. This study explored the effect of different diets on the volatile flavor and nutritional ingredients of O. vulgaris. Four diets were tested in four groups: Group A(fish(Scomberomorus niphonius)), Group B(crab(Helice tridens tientsinensis Rathbun)), Group C(clam(Mactra veneriformis)), and Group D(squid(Loligo japonica)). Octopus muscles were sampled after 36 days of feeding, and volatile flavor substances(VFSs), fatty acids(FAs), and amino acids(AAs) were detected. Results showed that the VFSs, FAs, and AAs of octopus in the four groups were obviously different. The sum of volatile ketones and aldehydes was higher in Group B than in the other groups, which could present much more flavors. All groups were abundant in unsaturated FAs, including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA). In terms of content and variety, the FAs in Group B were more beneficial to human health than those in the other groups. The content of each AA in Group B was basically higher than those in the other groups and was significantly higher than that in Group D(P < 0.05). Comparing the VFSs, FAs, and AAs in samples fed with four kinds of diets, the results indicate that using crab to feed O. vulgaris can achieve better effects on volatile flavor and nutritional ingredients.
文摘An unusual form of localized corrsion in copper tubes was detected early in service and in leakage tests after manufacturing.The morphology of this corrosion is similar to that of an ant's nest when viewed in cross section. The corrosion mechanisms, cases ofant's nest corrosion, and preventive measures are presented.
文摘Simultaneous distillation-extractor was used for extracting the volatile substances in Llex Kudincha.26 volatile components were identified by gas chromatography mass spectrometry (GC-MS)method.The identified compounds are 94.83 % of the total volatile substances.
基金funded by the national science and technology support plan ( 2011BAD17B03):Research and integrated demonstration of efficient production and utilization high quality forage of three gorges reservoir area
文摘[Objective] The aim was to provide theoretical basis for the exploitation and utilization of Trifolium. [Method] This paper introduced the main active ingredients,pharmacological effects and applications of Trifolium, and looked into research focus and direction in the future. [ Result] The main active ingredient of Trifolium is leaves protein concentration, isoflavones, chlorogenic acid and volatile substance. [ Conclusion] Trifolium resources in our country is abundant, which has been thought to be the most potential health food and new medical resources. It becomes research hotspot in the field of health food, biological medicine and related fields with its biological functions and pharmacological effects. We should strength- en the exploitation and utilization of Trifolium active ingredients apart from its forage function.
基金supported by the Academician Qi Faren Foundation project(No.2023):Space Remote Sensing Information Extreme Compression and Beidou Short Message Coupling System Technology.
文摘In lunar science,volatiles are defined as chemical elements and unstable compounds,evaporating,sublimating,or flowing in other ways at low temperature.At moderate temperature,volatiles transfers its flowing elements from solid materials to coexisting gas phases.Such substances include S,Cu,Zn,As,Se,Ag,Cd,In,Te,Hg,Ti,Pb,Bi,and halogens(F,C L,Br,and I).These volatile substances are mainly added by small impactors,so they should be uniformly deposited in lunar regolith.In the permanently shaded regions(PSRs)of the lunar polar region,the extremely low temperature may allow the solar activity record to be kept longer.When the lunar soil is heated,it will release volatile elements in the form of gas,especially the particles injected into the lunar soil by the solar wind.In deeper lunar soil,it means that these particles were implanted in different periods of solar evolution.The study of regolith in polar PSRs may help to solve this problem,because it has not been widely heated and therefore may not be subjected to postimplantation modification.The research on volatiles detection in lunar polar region can help us confirm the content and distribution of water ice in the permanent shadow region of the lunar polar region,and the composition,distribution,source,transport and loss mechanism of other volatiles in this region,as well as the relationship between lunar soil in the polar region and the ancient solar wind environment,and the environment and mineral resources in the region.Chandrayaan-3 provided important assistance to the conceptualization of this project.At the end of the article,we discussed the lunar orbit.
基金financial support from Primary Research&Development Plan of Hainan Province(NO:ZDYF2022XDNY335)Postgraduate Research&PracticeInnovation Program of Jiangsu Province(KYCX24_2633)+1 种基金Jiangsu Agricultural Industry Technology System(JATS[2023]464)Central Government Special Fund for Guiding Local Development(YDZX2022176).
文摘The presence of a fishy odor has emerged as a significant obstacle in the processing and commercialization of tilapia.In light of this,the present study employed ultrasonic-assisted enzyme deodorization to address this issue.The deodorization effects were evaluated from multiple perspectives,including chemical indexes(amino acid nitrogen content,trimethylamine content,and thiobarbituric acid value),physical indexes(texture),and sensory scores.Through the application of response surface methodology,an ultrasound-complex enzyme deodorization(UED)technology was ultimately optimized.The UED process resulted in a 56%reduction in trimethylamine content while also enhancing the taste,odor,and texture of the fish,thereby demonstrating its ability to significantly improve overall quality.Additionally,headspace solid-phase microextraction gas chromatographymass spectrometry(HS-SPME-GC/MS)and gas chromatography-ion mobility spectrometry(GC-IMS)were utilized to comprehensively analyze the impact of UED on flavor and elucidate its deodorization mechanism.Notably,UED samples exhibited reduced levels of components associated with undesirable fishy flavors such as hexanal,nonanal,1-octen-3-ol,and ethyl propanoate while experiencing an increase in components such as benzaldehyde,cis-Jasmone,and butyl lactate that contribute pleasant fruity and floral aromas.Overall,this study has developed an efficient convenient method for both deodorizing tilapia enhancing its aroma,making valuable contributions towards improving overall flavor profile tilapia products.
基金Universidade Federal Rural do Rio de Janeiro(UFRRJ),Empresa Brasileira de Pesquisa Agropecuária(Embrapa)and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior(CAPES)for their financial support(1020010/00542).
文摘Coffee is currently the second largest commodity on the world market today,and there is great concern about the quality of the beans exported from producer countries to Europe and USA.Practices such as using blends of different species and adding low-cost raw materials,such as chicory,corn,and soybean,impair the sensory and functional characteristics of the drink made from roasted and ground coffee beans.There is a need to adopt more efficient analytical methods than the microscopy technique currently used.The first chromatographic method used to determine fraud was reported in 1958.This method used paper chromatography to differentiate between coffee and chicory based on the free reducing sugars.As of the 1980s,different methods involving high-performance liquid chromatography and gas chromatography were developed in order to demonstrate geographic authenticity,distinction between species,occurrence of adulteration,and the presence of defective beans by determining the monosaccharides,oligosaccharides,tocopherols,fatty acids,volatiles,diterpenes,sterols,and phenolic substances,among others.As far as the authors know,there are no papers published in the literature that have compiled such an extensive set of information about these chromatographic methods as here.Over the last 2 years,there has been a trend to develop analytical methods for ultra-performance liquid chromatography coupled with tandem mass spectrometry to confirm fraud in coffee,due to high sensitivity and selectivity.
基金financial support from multiple sources,including the National Natural Science Foundation of China(32072987)the National Key R.&D.Program of China(2023YFD2402000)+1 种基金the earmarked fund for CARS-48K.C.Wong Magna Fund in Ningbo University.
文摘A six-week feeding trial was carried out to determine the feasibility of cottonseed oil(CSO)as a viable substitute for fish oil(FO)in the commercial diet of swimming crabs.Ninety healthy swimming crabs(initial body weight 34.28±0.59 g)were randomly assigned to 90 plastic baskets.Three isonitrogenous and isolipidic diets(450 g/kg protein and 120 g/kg lipid)were formulated replacing FO with CSO at 0%,50%and 100%(CSO-0,CSO-50,and CSO-100),respectively.Each diet was randomly allocated to three replicates,each consisting of 10 crabs.Results indicated that crabs fed with CSO-100 diet had the lowest the percent weight gain(PWG),specific growth rate(SGR)and survival among all treatments(P<0.05).Albumin(ALB),glucose(GLU),triglyceride(TAG),total cholesterol(T-CHO),low-density lipoprotein cholesterol(LDL-C),non-esterified fatty acid(NEFA)contents and alkaline phosphatase(ALP),alanine amino transferase(ALT)activity in hemolymph were significantly affected by dietary substitution of FO with CSO(P<0.05).The contents of total saturated fatty acids(SFA),total mono-unsaturated fatty acids(MUFA)and total long-chain polyunsaturated fatty acids(LC-PUFA)in the hepatopancreas and muscle were negatively correlated with the substitution level,whereas total n-6 polyunsaturated fatty acids(n-6 PUFA)and linoleic acid(18:2n-6)contents increased significantly with increasing levels of dietary substitution of FO with CSO(P<0.05).Dietary substitution of FO with CSO resulted in changes in the composition of volatile substances in muscle,with 16 volatile substances in muscle significantly affected(P<0.05).The relative expression of genes related to lipid synthesis such as fatty acid synthase(fas),acetyl-CoA carboxylase(acc)and glycerol-3-phosphate acyltransferase 1(gpat1)in the hepatopancreas were significantly up-regulated in the CSO-50 group compared to other treatment groups(P<0.05).The relative expression of fatty acid anabolism-related genes fatty acyl desaturase 2(fads2)and elongase 4(elovl4)were significantly down-regulated with the increase of dietary substitution of FO with CSO(P<0.05).In conclusion,50%substitution with CSO had no negative effects on growth performance,promoted lipid synthesis and metabolism,facilitated lipid accumulation.However,complete substitution of FO with CSO inhibited fatty acid synthesis and metabolism,resulting in a lower tissue LC-PUFA content and an altered composition of muscle volatiles.
基金supported by“The National Key R&D Program”(2022YFF1100400).
文摘We evaluated the changes in volatile and nonvolatile flavor substances after fermented milk was fermented by Lacticaseibacillus rhamnosus WH.FH-19 using Headspace Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry(HS-SPME-GC-MS)and High-Performance Liquid Chromatography-Mass Spectrometry(HPLC-MS).The results have shown that the addition of L.rhamnosus WH.FH-19 can increase the contents of acetoin and 2-nonanone which can give fermented milk cream and cheese flavor,and significantly enrich amino acid meta-bolism and carbon metabolism.The fermentation of L.rhamnosus WH.FH-19 increased the contents of L-glu-tamic acid,taurine,stachyose,erythritol,L-rhamnose,retinol,pantothenic acid and 19 oligopeptides in fermented milk,and endowed fermented milk with good flavor,quality and antioxidant capacity.The results presented that L.rhamnosus WH.FH-19 can increase the content of flavor substances,promote the metabolism of amino acids and carbohydrates in fermented milk,and produce more antioxidant metabolites,which had the potential as a starter of fermented milk.
基金financial support from National Key R&D Program of China(Contract No.2017YFD0400501)the 111 Project(BP0719028)+1 种基金National First-class Discipline Program of Food Science and Technology(No.JUFSTR20180205)Jiangsu Province Key Laboratory Project of Advanced Food Manufacturing Equipment and Technology(No.FMZ202003)。
文摘The undesirable odor of crab meatballs was evident after boiling and cooling,high-voltage electrostatic field(HVEF),lysozyme and yeast extract(LY),and the combination(LYH)were all applied to pre-deodorize crab meatballs to estimate the effect in view of odor,pH,fat oxidation and protein oxidation.None of the tert-butylamine(1.58±0.14 ng/g),(E,E)-2,4-Dodecadienal(18.52±0.12 ng/g),1-Octen-3-ol(13.51±0.22 ng/g)and nonanal(681.55±0.24 ng/g)in the control were detected in LYH group,while nonanal in HVEF and LY groups was reduced by 86.07%and 42.60%,respectively.Thirteen volatile substances with variable importance plot≥1 contributed prominently to the odor of crab meatballs depended on partial least squares discrimination analysis.Protein oxidation of the pretreated crab meatballs was alleviated,as well as thiobarbituric acid reactive substances(TBARS)and lipoxygenase(LOX)activity,with the best inhibitory effect of LYH being 40.10%and 62.80%on the respective effects.The correlation analysis derived that fishy substances were significantly positively correlated with TBARS and pH.LYH was the optimal pre-deodorization,which involved promoting glycolysis and lactic acid bacteria colonization in the liquid medium,and inhibiting fat oxidation by affecting enzyme activity in HVEF.
基金supported by The Key R&D Program of Shaanxi Province,China(2023-ZDLNY-43).
文摘The primary objective of this study was to investigate the effect of fermentation with Lactobacillus acidophilus 6074 on the nutrient transformation and quality characteristics of jujube juice.The screened L.acidophilus 6074 with acid and bile salt resistance was used to ferment jujube juice,and the sensory properties and nutrient biotransformation of the fermented product were comprehensively evaluated.The results showed that the acid and bile salt resistance of L.acidophilus 6074 were 94.06%and 84.56%,respectively,and the viable counts after fermentation reached 8.75 lg CFU/mL.Total sugar and polysaccharide content decreased after fermentation,while total flavonoids,cAMP and triterpenoic acid increased significantly,as did organic acids and free amino acids(p<0.05).Moreover,the L.acidophilus 6074 fermentation reduced the molecular weight of the main polysaccharide component from 746,111.957 Da to 573,809.851 Da,and its microstructure changed.A total of 62 volatile compounds were identified in fermented jujube juice,among which acids were the highest,followed by esters.Particularly,L.acidophilus 6074 fermentation increased the content of phenylethyl acetate and lactic acid,generating new substances clopenthixol and phenylethyl alcohol of jujube juice.Sensory evaluation indicated that L.acidophilus 6074 fermentation improved the coloration of jujube juice and increased the overall acceptability of the fermented product.This study will provide theoretical basis and technical support for the industrial production of probiotic fermentation jujube juice related products.
