This study evaluated the contribution of three spoilage bacteria(Shewanella putrefaciens(S.putrefaciens),Pseu-domonas fluorescens(P.fluorescens),and Aeromonas salmonicida(A.salmonicida))to the degradation of adenosine...This study evaluated the contribution of three spoilage bacteria(Shewanella putrefaciens(S.putrefaciens),Pseu-domonas fluorescens(P.fluorescens),and Aeromonas salmonicida(A.salmonicida))to the degradation of adenosine triphosphate(ATP)-related compounds in fish juice and fillet systems of large yellow croaker during cold chain logistics.The contribution of spoilage bacteria was explored by determining the microbial counts,ATP-related compounds,and associated enzyme activities.The results revealed that the S.putrefaciens,P.fluorescens,and A.salmonicida have the highest activities in 5′-nucleotidase(5′-NT),acid phosphatase(ACP),and alkaline phosphatase(AKP),with 49.78,162.24,and 142.3 U/gprot,respectively.The rapid degradation of inosine monophosphate(IMP)occurs with increasing 5′-NT activity.It indicates that S.putrefaciens,P.fluorescens,and A.salmonicida mainly secreted 5′-NT,ACP,and AKP to degrade IMP,respectively,and that 5′-NT was the key enzyme in degrading IMP.All three are notable producers of purine nucleoside phosphorylase(PNP)and xanthine oxidase(XOD).The results showed that S.putrefaciens is the primary bacterium in the pre-degradation phase of ATP-related compounds,and A.salmonicida presumably dominates in the post-degradation phase.This study offers critical insights into the research on spoilage mechanisms of marine fish throughout the cold chain logistics.展开更多
This research aimed to study the evolution of ATP-related compounds in dry-cured ham and to assess their suitability as chemical markers of food contamination.A rapid high-performance liquid chromatography(HPLC)method...This research aimed to study the evolution of ATP-related compounds in dry-cured ham and to assess their suitability as chemical markers of food contamination.A rapid high-performance liquid chromatography(HPLC)method was developed for the analysis of five ATP-related compounds namely,ATP,ADP,AMP,hypoxanthine,and Ino in sliced dry-cured ham.Moreover,a positive correlation between ATP content and microbial load was found in ham during storage.In addition,the method developed herein was employed to quantify ATP-related compounds in sliced dry-cured ham wrapped in a novel antibacterial packaging film containing the cell-free supernatant(CFS)of a probiotic Lactiplantibacillus plantarum strain.The contents of ATP-related compounds in ham samples wrapped in the antibacterial packaging film were lower than in control samples during the 7 days of storage(181 vs 269 mg/kg on day 2;247 vs 286 mg/kg on day 5;272 vs 297 mg/kg on day 7).Thus,the evaluated CFS could be considered in packaging material applications for the preservation of sliced ham.This study presents an effective method to assess the quality of sliced ham,which might also contribute to the adoption of active packaging in the food industry.展开更多
To study the changes of volatile compounds and antioxidant activity of fast fermented shrimp head paste during the fermentation processing,Penaeus vannamei boone head was used as the raw material,and compound starter ...To study the changes of volatile compounds and antioxidant activity of fast fermented shrimp head paste during the fermentation processing,Penaeus vannamei boone head was used as the raw material,and compound starter was added for fermen-tation.During the 14 days of fermentation,the changes of free amino acids,volatile flavor compounds and main components were determined by SPME-GC-MS and electronic nose.The oxidation-resistance changes of water extract at different fermentation stages were evaluated.The results showed that the total free amino acids increased from original 2320 to 5640 mg(100 mL)^(−1).SPME-GC-MS analysis found that aldehydes,pyrazine compounds increased from 10.80%,1.94%to 24.35%,13.63%respectively during the fermentation process.The HO·scavenging ability of shrimp head paste increased from 52%to 86%.Our results showed that the shrimp paste produced from shrimp head fermentation could obtain good flavor and possess certain antioxidant activity of aquatic fermented condiment.展开更多
The quality and flavor of scallops changes during the fresh dry rehydration process.In order to control the changes after rehydration,a scallop pretreatment method was adopted.The pretreatment method involved impregna...The quality and flavor of scallops changes during the fresh dry rehydration process.In order to control the changes after rehydration,a scallop pretreatment method was adopted.The pretreatment method involved impregnating fresh scallops with 0.2 g/100 m L konjac glucomannan(KGM),carrageenan(CA),and sodium alginate(SA)before the drying and rehydration process.After rehydration,the KGM treated samples had better water retention and the highest betaine content.The CA treated samples had a deepened yellow color and the highest content of flavoring amino acids(FAA)and inosine monophosphate(IMP).What’s more,a total of 77 volatile compounds were detected,with a maximum of 15 esters.The highest proportion in the four groups was eugenol,followed by n-hexadecanoic acid,methyl hexadecanoate etc.The SA group had no significant contribution in terms of quality and taste.The samples pretreated with KGM had the best quality,and those pretreated by CA had the best flavor.展开更多
The quality changes of shelled Pacific oysters(Crassostrea gigas)were examined in relation to the effects of superchilling storage at-1 C for 28 d by measuring changes in biochemical properties(microbial analysis,aden...The quality changes of shelled Pacific oysters(Crassostrea gigas)were examined in relation to the effects of superchilling storage at-1 C for 28 d by measuring changes in biochemical properties(microbial analysis,adenosine triphosphate(ATP)-related compounds,pH,free amino acids)and sensory evaluations in this study.The results indicated that microorganism growth was significantly inhibited during superchilling storage.Adenosine diphosphate(ADP)and adenosine monophosphate(AMP)accumulated while ATP rapidly decreased in the adductor muscle.ATP and ADP were the primary components in the other 3 tissues including mantle,gill,and body trunk of oysters,and they remained relatively stable over time.The pH and adenylate energy charge in the adductor muscle could be utilized as freshness indicators for shelled oysters.However,there were no significant differences(P>0.05)among the free amino acids during whole storage.According to the sensory evalu-ations,oysters could be alive and tolerated up to 21 d at-1℃storage.The study demonstrated that superchilling storage at-1℃could better maintain the eating quality of shelled oysters and the shelf life was extended to 21 d.展开更多
Microbial activity is the primary and inevitable factor contributing to seafood spoilage.To assess the spoilage potential of dominant bacteria(Hafnia paralvei and Aeromonas allosaccharophila)isolated from spoiled vacu...Microbial activity is the primary and inevitable factor contributing to seafood spoilage.To assess the spoilage potential of dominant bacteria(Hafnia paralvei and Aeromonas allosaccharophila)isolated from spoiled vacuum-packed grouper fillets under cold storage.In this study,the total viable count(TVC),total volatile basic nitrogen(TVB-N),pH,trichloroacetic acid(TCA)-soluble peptides,water-holding capacity(WHC),nucleotide catabolism,free amino acids(FAAs),and volatile compounds(VOCs)of grouper fillets in vacuum packaging under cold storage with different bacteria inoculated(H.paralvei inoculated,A.allosaccharophila inoculated,and H.paralvei&A.allosaccharophila inoculated)were characterized.The results revealed that H.paralvei exhibited stronger degradation activity,leading to decreased water-holding capacity and increased levels of TVB-N and TCA-soluble peptides.Amino acid analysis showed distinct metabolic patterns for H.paralvei and A.allosaccharophila,with H.paralvei showing a high potential for utilizing FAAs.Both H.paralvei and A.allosaccharophila caused nucleotide catabolism,but A.allosaccharophila produced more hypoxanthine riboside and hypoxanthine.In addition,the analysis of VOCs indicated that H.paralvei produces large content of aldehydes in the middle of storage,particularly benzaldehyde.In addition,the grouper fillets inoculated with H.paralvei&A.allosaccharophila showed similar physicochemical changes to that inoculated with H.paralvei.In conclusion,H.paralvei emerged as the key bacteria responsible for spoilage in vacuum-packed grouper.This study is helpful in further understanding the relationship between spoilage microorganisms and the quality of grouper fillets,thereby providing valuable information for their preservation.展开更多
基金supported by the National Natural Science Foundation of China(32302174)the earmarked fund for China Agriculture Research System of MOF and MARA(CARS-47)the Shanghai Professional Technology Service Platform on Cold Chain Equipment Perfor-mance and Energy Saving Evaluation(19DZ2284000).
文摘This study evaluated the contribution of three spoilage bacteria(Shewanella putrefaciens(S.putrefaciens),Pseu-domonas fluorescens(P.fluorescens),and Aeromonas salmonicida(A.salmonicida))to the degradation of adenosine triphosphate(ATP)-related compounds in fish juice and fillet systems of large yellow croaker during cold chain logistics.The contribution of spoilage bacteria was explored by determining the microbial counts,ATP-related compounds,and associated enzyme activities.The results revealed that the S.putrefaciens,P.fluorescens,and A.salmonicida have the highest activities in 5′-nucleotidase(5′-NT),acid phosphatase(ACP),and alkaline phosphatase(AKP),with 49.78,162.24,and 142.3 U/gprot,respectively.The rapid degradation of inosine monophosphate(IMP)occurs with increasing 5′-NT activity.It indicates that S.putrefaciens,P.fluorescens,and A.salmonicida mainly secreted 5′-NT,ACP,and AKP to degrade IMP,respectively,and that 5′-NT was the key enzyme in degrading IMP.All three are notable producers of purine nucleoside phosphorylase(PNP)and xanthine oxidase(XOD).The results showed that S.putrefaciens is the primary bacterium in the pre-degradation phase of ATP-related compounds,and A.salmonicida presumably dominates in the post-degradation phase.This study offers critical insights into the research on spoilage mechanisms of marine fish throughout the cold chain logistics.
基金financially supported by the Key Research Projects of the Science and Technology Department of Henan Province(No.222102110352)the Doctor fund project of Zhengzhou University of Light Industry(No.2022BSJJZK08).
文摘This research aimed to study the evolution of ATP-related compounds in dry-cured ham and to assess their suitability as chemical markers of food contamination.A rapid high-performance liquid chromatography(HPLC)method was developed for the analysis of five ATP-related compounds namely,ATP,ADP,AMP,hypoxanthine,and Ino in sliced dry-cured ham.Moreover,a positive correlation between ATP content and microbial load was found in ham during storage.In addition,the method developed herein was employed to quantify ATP-related compounds in sliced dry-cured ham wrapped in a novel antibacterial packaging film containing the cell-free supernatant(CFS)of a probiotic Lactiplantibacillus plantarum strain.The contents of ATP-related compounds in ham samples wrapped in the antibacterial packaging film were lower than in control samples during the 7 days of storage(181 vs 269 mg/kg on day 2;247 vs 286 mg/kg on day 5;272 vs 297 mg/kg on day 7).Thus,the evaluated CFS could be considered in packaging material applications for the preservation of sliced ham.This study presents an effective method to assess the quality of sliced ham,which might also contribute to the adoption of active packaging in the food industry.
基金supported by the National Na-tural Science Foundation of China(Nos.32072348 and 31671825)the Open Project Program of Beijing Key Laboratory of Flavor Chemistry(No.SPFW2019YB01).
文摘To study the changes of volatile compounds and antioxidant activity of fast fermented shrimp head paste during the fermentation processing,Penaeus vannamei boone head was used as the raw material,and compound starter was added for fermen-tation.During the 14 days of fermentation,the changes of free amino acids,volatile flavor compounds and main components were determined by SPME-GC-MS and electronic nose.The oxidation-resistance changes of water extract at different fermentation stages were evaluated.The results showed that the total free amino acids increased from original 2320 to 5640 mg(100 mL)^(−1).SPME-GC-MS analysis found that aldehydes,pyrazine compounds increased from 10.80%,1.94%to 24.35%,13.63%respectively during the fermentation process.The HO·scavenging ability of shrimp head paste increased from 52%to 86%.Our results showed that the shrimp paste produced from shrimp head fermentation could obtain good flavor and possess certain antioxidant activity of aquatic fermented condiment.
基金funded by the National Key R&D Program of China(2020YFD0900900)。
文摘The quality and flavor of scallops changes during the fresh dry rehydration process.In order to control the changes after rehydration,a scallop pretreatment method was adopted.The pretreatment method involved impregnating fresh scallops with 0.2 g/100 m L konjac glucomannan(KGM),carrageenan(CA),and sodium alginate(SA)before the drying and rehydration process.After rehydration,the KGM treated samples had better water retention and the highest betaine content.The CA treated samples had a deepened yellow color and the highest content of flavoring amino acids(FAA)and inosine monophosphate(IMP).What’s more,a total of 77 volatile compounds were detected,with a maximum of 15 esters.The highest proportion in the four groups was eugenol,followed by n-hexadecanoic acid,methyl hexadecanoate etc.The SA group had no significant contribution in terms of quality and taste.The samples pretreated with KGM had the best quality,and those pretreated by CA had the best flavor.
基金supported by the Japan Society for the Promotion of Science(19H05611).
文摘The quality changes of shelled Pacific oysters(Crassostrea gigas)were examined in relation to the effects of superchilling storage at-1 C for 28 d by measuring changes in biochemical properties(microbial analysis,adenosine triphosphate(ATP)-related compounds,pH,free amino acids)and sensory evaluations in this study.The results indicated that microorganism growth was significantly inhibited during superchilling storage.Adenosine diphosphate(ADP)and adenosine monophosphate(AMP)accumulated while ATP rapidly decreased in the adductor muscle.ATP and ADP were the primary components in the other 3 tissues including mantle,gill,and body trunk of oysters,and they remained relatively stable over time.The pH and adenylate energy charge in the adductor muscle could be utilized as freshness indicators for shelled oysters.However,there were no significant differences(P>0.05)among the free amino acids during whole storage.According to the sensory evalu-ations,oysters could be alive and tolerated up to 21 d at-1℃storage.The study demonstrated that superchilling storage at-1℃could better maintain the eating quality of shelled oysters and the shelf life was extended to 21 d.
基金supported by the National Natural Science Foundation of China(31972142)China Agriculture Research System of MOF and MARA(CARS-47)Shanghai Municipal Science and Technology Project to Enhance the Capabilities of the Platform(20DZ2292200,19DZ2284000).
文摘Microbial activity is the primary and inevitable factor contributing to seafood spoilage.To assess the spoilage potential of dominant bacteria(Hafnia paralvei and Aeromonas allosaccharophila)isolated from spoiled vacuum-packed grouper fillets under cold storage.In this study,the total viable count(TVC),total volatile basic nitrogen(TVB-N),pH,trichloroacetic acid(TCA)-soluble peptides,water-holding capacity(WHC),nucleotide catabolism,free amino acids(FAAs),and volatile compounds(VOCs)of grouper fillets in vacuum packaging under cold storage with different bacteria inoculated(H.paralvei inoculated,A.allosaccharophila inoculated,and H.paralvei&A.allosaccharophila inoculated)were characterized.The results revealed that H.paralvei exhibited stronger degradation activity,leading to decreased water-holding capacity and increased levels of TVB-N and TCA-soluble peptides.Amino acid analysis showed distinct metabolic patterns for H.paralvei and A.allosaccharophila,with H.paralvei showing a high potential for utilizing FAAs.Both H.paralvei and A.allosaccharophila caused nucleotide catabolism,but A.allosaccharophila produced more hypoxanthine riboside and hypoxanthine.In addition,the analysis of VOCs indicated that H.paralvei produces large content of aldehydes in the middle of storage,particularly benzaldehyde.In addition,the grouper fillets inoculated with H.paralvei&A.allosaccharophila showed similar physicochemical changes to that inoculated with H.paralvei.In conclusion,H.paralvei emerged as the key bacteria responsible for spoilage in vacuum-packed grouper.This study is helpful in further understanding the relationship between spoilage microorganisms and the quality of grouper fillets,thereby providing valuable information for their preservation.
