The milk fat globule membrane(MFGM)is a complex structure with numerous functions,and its composition is affected by many factors.There have been few systematic investigations on goat MFGM proteome profiling during la...The milk fat globule membrane(MFGM)is a complex structure with numerous functions,and its composition is affected by many factors.There have been few systematic investigations on goat MFGM proteome profiling during lactation.Individual milk samples from 15 healthy dairy goats were obtained at six lactation time points for investigation of the MFGM proteome using both data-independent acquisition(DIA)and data-dependent acquisition(DDA)proteomics techniques combined with multivariate statistical analysis.Using the DIA method,890 variably abundant MFGM proteins were discovered throughout the lactation cycle.From 1 to 240 d,butyrophilin subfamily 1 member A1,lipoprotein lipase,perilipin-2,and adipose triglyceride lipase were upregulated,while APOE,complement C3,clusterin,and IgG were downregulated.Furthermore,from 1 to 90 d,annexin A1,annexin A2,and antithrombin-ll were downregulated,then upregulated by d 240.Albumin had a high degree of connectedness,indicating that it was a key protein,according to protein-protein interaction research.Overall,our findings gave new insights into the biological features of MFGM protein in goat milk throughout lactation,which may aid in the creation of specialized MFGM products and infant formula.展开更多
The objective of the present study was to develop models for egg freshness and shelf-life predictions for the selected evaluation indicators including egg weight,Flaugh unit(HU),and albumen height.Experiments were car...The objective of the present study was to develop models for egg freshness and shelf-life predictions for the selected evaluation indicators including egg weight,Flaugh unit(HU),and albumen height.Experiments were carried out at different storage temperatures for a total period of 29-32 d.All data were collected and fitted in to Arrhenius equation for egg freshness,while the HU data were applied to a probability model for shelf-life prediction.The results showed that egg weight,albumen height,and HU decreased significantly,while albumen pH increased with the extension of storage time.The higher the storage temperature,the faster the egg quality decreased.In addition,the bias factor,accuracy factor,and the standard error of prediction were selected to verify the developed quality models.Maximum rescaled R-square statistic,the Hosmer-Lemeshow goodness-of-fit statistic,and the receiver operating characteristic curve were used to evaluate the goodness-of-fit of the developed probability model for the shelf-life of eggs,which indicated that the presented predictive models can be used to assess egg freshness and predict shelf-life during different storage temperatures.展开更多
Milk fatty acids significantly contribute to human nutrition and clinical health.However,previous evidence for changes in the fatty acid profiles of different dairy species following homogenization and heat treatment ...Milk fatty acids significantly contribute to human nutrition and clinical health.However,previous evidence for changes in the fatty acid profiles of different dairy species following homogenization and heat treatment is lacking.Here,changes in fat globule particle size and fatty acids in samples of Holstein,goat,buffalo,yak,and camel milk following homogenization(20 MPa)and heat treatment(63℃for 30 min and 90℃for 15 min)were investigated using a laser particle sizer and gas chromatography approach.The results indicated that the milk fat globule particle size of all studied dairy species significantly decreased after homogenization and heat treatment,in which there was no difference.The fatty acid composition of C10:0 and medium-chain fatty acid in goat milk,Ci8:0 and long-chain fatty acid in camel milk,and C16:0 in buffalo and yak milk served as the characteristic traits of these milks.Changes in the relative contents of several fatty acids(C4:0,C10:0,C16:0,C18:0,C18:1n9c,and C18:3n3)were dependent on homogenization,heat treatment,and the type of dairy species.In particular,C18:3n3 significantly decreased in goat and camel milk after homogenization and heat treatment.These findings provide new insights into how homogenization and heat treatment affect the fatty acid profile and can be used to further improve the heat treatment of milk from minor dairy species.展开更多
The aim of this study was to examine the effectiveness of plasma-activated water(PAW)for inactivating Escherichia coli(E.col)and retention of key quality factors for kale.Different plasma discharge times(1,2,3,4,5,and...The aim of this study was to examine the effectiveness of plasma-activated water(PAW)for inactivating Escherichia coli(E.col)and retention of key quality factors for kale.Different plasma discharge times(1,2,3,4,5,and 10 min)and different exposure times(2,4,6,8,10,and 15 min)were used to investigate the inactivation effect of E.coli spot-inoculated on kale.The influence of different exposure times on the pH,hardness and color of kale was studied post-treatment.In addition,the effects of PAW on the shelf-life of kale over 12 d of storage at 4℃ were investigated.The results showed that after the treatment of 5-PAW-8(8 min treatment by PAW generated by 5 min plasma discharge),the population of E.coli on kale was reduced by approximately 1.55 log colony-forming units(CFU)/g and the changes in pH,hardness and color of kale were not significant(P>0.05).During the storage period after 5-PAW-8 treatment,the hardness,weight loss,color,surface morphology and ascorbic acid were found to be better than those of the two control groups(P<0.05).Furthermore,no significant changes were observed in pH values,the content of total phenols,or 1,1-dipheny1-2-picrylhydrazyl radical scavenging capacity(P>0.05).It is indicated that PAW treatment is a promising methodfor improving microbiological safety and extending the shelf-life of kale.展开更多
The heat-induced formation of molecular polymers betweenβ-lactoglobulin(β-LG)and the milk fat globule membrane(MFGM)has been widely recognized;nevertheless,the molecular mechanisms underlying this formation remain u...The heat-induced formation of molecular polymers betweenβ-lactoglobulin(β-LG)and the milk fat globule membrane(MFGM)has been widely recognized;nevertheless,the molecular mechanisms underlying this formation remain unclear.This study aimed to investigate the binding mechanisms and physicochemical properties of complexes formed betweenβ-LG and MFGM under two distinct heat treatment conditions:63℃for 30 min and 90℃for 15 min.Differential scanning calorimetry analysis indicated that heating the complexes at 90℃for 15 min enhanced their thermal stability.Following this treatment,MFGM-protein complexes exhibited decreased intrinsic fluorescence intensity and a blue shift in the maximum emission wavelength.To elucidate the molecular mechanisms underlying complex formation,blocking agents including dithiobis-nitrobenzoic acid,N-ethylmaleimide,and dithioerythritol were applied at both 63℃/30 min and 90℃/15 min,followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.The results demonstrate thatβ-LG-MFGM complex formation involves disulfide bonds(notably Cys~(121)),hydrogen bonding,hydrophobic interactions,and electrostatic interactions,in addition to general intermolecular forces.Heat treatment was found to promote both the formation and thermal stability of these complexes.These findings provide a mechanistic basis for further investigation of how heat processing influences the digestive behavior and functional properties ofβ-LG-MFGM complexes.展开更多
基金This work was supportedby theNational KeyR&D Program of China(2022YFD1301005)the Shandong Provincial Natural Science Foundation,China(ZR2022MC184)the High-level Talents Foundation of Qingdao Agricultural University,China(665/1120053,665/1120080).
文摘The milk fat globule membrane(MFGM)is a complex structure with numerous functions,and its composition is affected by many factors.There have been few systematic investigations on goat MFGM proteome profiling during lactation.Individual milk samples from 15 healthy dairy goats were obtained at six lactation time points for investigation of the MFGM proteome using both data-independent acquisition(DIA)and data-dependent acquisition(DDA)proteomics techniques combined with multivariate statistical analysis.Using the DIA method,890 variably abundant MFGM proteins were discovered throughout the lactation cycle.From 1 to 240 d,butyrophilin subfamily 1 member A1,lipoprotein lipase,perilipin-2,and adipose triglyceride lipase were upregulated,while APOE,complement C3,clusterin,and IgG were downregulated.Furthermore,from 1 to 90 d,annexin A1,annexin A2,and antithrombin-ll were downregulated,then upregulated by d 240.Albumin had a high degree of connectedness,indicating that it was a key protein,according to protein-protein interaction research.Overall,our findings gave new insights into the biological features of MFGM protein in goat milk throughout lactation,which may aid in the creation of specialized MFGM products and infant formula.
基金supported by the Key Research and Development Program of Shandong Province(No.2019GNC106024)the Shandong Poultry Industry Innovation Team Construction Project(SDAIT-11-14)the High-level Talent Research Fund of Qingdao Agricultural University(No.6631120080/1111317),China.
文摘The objective of the present study was to develop models for egg freshness and shelf-life predictions for the selected evaluation indicators including egg weight,Flaugh unit(HU),and albumen height.Experiments were carried out at different storage temperatures for a total period of 29-32 d.All data were collected and fitted in to Arrhenius equation for egg freshness,while the HU data were applied to a probability model for shelf-life prediction.The results showed that egg weight,albumen height,and HU decreased significantly,while albumen pH increased with the extension of storage time.The higher the storage temperature,the faster the egg quality decreased.In addition,the bias factor,accuracy factor,and the standard error of prediction were selected to verify the developed quality models.Maximum rescaled R-square statistic,the Hosmer-Lemeshow goodness-of-fit statistic,and the receiver operating characteristic curve were used to evaluate the goodness-of-fit of the developed probability model for the shelf-life of eggs,which indicated that the presented predictive models can be used to assess egg freshness and predict shelf-life during different storage temperatures.
基金the High-level Talents Foundation of Qingdao Agricultural University(665/1120053)Shandong Provincial Science and Technology Foundation,China(YDZX2021111)Qingdao science and technology demonstration and guidance project(21-1-4-ny-17-nsh),China.
文摘Milk fatty acids significantly contribute to human nutrition and clinical health.However,previous evidence for changes in the fatty acid profiles of different dairy species following homogenization and heat treatment is lacking.Here,changes in fat globule particle size and fatty acids in samples of Holstein,goat,buffalo,yak,and camel milk following homogenization(20 MPa)and heat treatment(63℃for 30 min and 90℃for 15 min)were investigated using a laser particle sizer and gas chromatography approach.The results indicated that the milk fat globule particle size of all studied dairy species significantly decreased after homogenization and heat treatment,in which there was no difference.The fatty acid composition of C10:0 and medium-chain fatty acid in goat milk,Ci8:0 and long-chain fatty acid in camel milk,and C16:0 in buffalo and yak milk served as the characteristic traits of these milks.Changes in the relative contents of several fatty acids(C4:0,C10:0,C16:0,C18:0,C18:1n9c,and C18:3n3)were dependent on homogenization,heat treatment,and the type of dairy species.In particular,C18:3n3 significantly decreased in goat and camel milk after homogenization and heat treatment.These findings provide new insights into how homogenization and heat treatment affect the fatty acid profile and can be used to further improve the heat treatment of milk from minor dairy species.
基金supported by the Grants from the China NationalCenterfor Food Safety Risk Assessment (No.20210349-6602421216)the Qingdao Science and Technology Demonstration and Guidance Project (No.21-1-4-ny-17-nsh)the High-level Talent Research Fund of Qingdao Agricultural University (No.6631115043),China。
文摘The aim of this study was to examine the effectiveness of plasma-activated water(PAW)for inactivating Escherichia coli(E.col)and retention of key quality factors for kale.Different plasma discharge times(1,2,3,4,5,and 10 min)and different exposure times(2,4,6,8,10,and 15 min)were used to investigate the inactivation effect of E.coli spot-inoculated on kale.The influence of different exposure times on the pH,hardness and color of kale was studied post-treatment.In addition,the effects of PAW on the shelf-life of kale over 12 d of storage at 4℃ were investigated.The results showed that after the treatment of 5-PAW-8(8 min treatment by PAW generated by 5 min plasma discharge),the population of E.coli on kale was reduced by approximately 1.55 log colony-forming units(CFU)/g and the changes in pH,hardness and color of kale were not significant(P>0.05).During the storage period after 5-PAW-8 treatment,the hardness,weight loss,color,surface morphology and ascorbic acid were found to be better than those of the two control groups(P<0.05).Furthermore,no significant changes were observed in pH values,the content of total phenols,or 1,1-dipheny1-2-picrylhydrazyl radical scavenging capacity(P>0.05).It is indicated that PAW treatment is a promising methodfor improving microbiological safety and extending the shelf-life of kale.
基金supported by the National Key Research and Development Program of China(No.2022YFD1301000)the National Center of Technology Innovation for Dairy(No.2024-FWPT-001)+1 种基金the Qingdao Agricultural University Haidu College Research Project Fund(No.KY202305)the Qingdao Science and Technology Benefiting the People Demonstration Project(No.25-1-5-xdny-32-nsh),China。
文摘The heat-induced formation of molecular polymers betweenβ-lactoglobulin(β-LG)and the milk fat globule membrane(MFGM)has been widely recognized;nevertheless,the molecular mechanisms underlying this formation remain unclear.This study aimed to investigate the binding mechanisms and physicochemical properties of complexes formed betweenβ-LG and MFGM under two distinct heat treatment conditions:63℃for 30 min and 90℃for 15 min.Differential scanning calorimetry analysis indicated that heating the complexes at 90℃for 15 min enhanced their thermal stability.Following this treatment,MFGM-protein complexes exhibited decreased intrinsic fluorescence intensity and a blue shift in the maximum emission wavelength.To elucidate the molecular mechanisms underlying complex formation,blocking agents including dithiobis-nitrobenzoic acid,N-ethylmaleimide,and dithioerythritol were applied at both 63℃/30 min and 90℃/15 min,followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.The results demonstrate thatβ-LG-MFGM complex formation involves disulfide bonds(notably Cys~(121)),hydrogen bonding,hydrophobic interactions,and electrostatic interactions,in addition to general intermolecular forces.Heat treatment was found to promote both the formation and thermal stability of these complexes.These findings provide a mechanistic basis for further investigation of how heat processing influences the digestive behavior and functional properties ofβ-LG-MFGM complexes.
