Study On The Influence Of Heat Treatment And Barrier Packaging On The Quality Of Braised Pork

Braised pork is a typical Chinese dish that is popular with people.In recent years,a number of researchers mainly focus on the process of cuisine making,but there is little research on flexible packaging products.Heat treatment,vacuum packaging,and reheating are necessary for industrial production and consumption of vacuum flexible package braised pork that can be stored at room temperature.Therefore,based on the previous research,the research on the quality maintenance of braised pork and determine the appropriate heat treatment packaging materials and reheating methods that have less effect on the flavor and taste of braised pork would be continued.The research results are as follows:?1?Effects of heat treatment combination on the quality of braised porkThe group simmering for 60 minutes used as a control,compared the differences between the five treatment groups of 0 min,15 min,30 min,45 min,and 60 min.sterilization at 121°C and 20 minutes to determine the process closest to the traditional practice of braised pork.The color of the samples in the group simmered 45 min+sterilized and simmered 60 min+sterilized was closest to the control group;the cohesiveness and springiness of the fat and skin of group simmered 45 min+sterilized and simmered 60 min+sterilized were closest to the control group;The results of the electronic nose determination of the samples in group simmered 45 min+sterilized was closest to the control group;sterilization and simmering would reduce the content of free amino acids in the samples;the sensory score of the group simmered 45 min+sterilized was highest in each treatment group.In summary,the results of the braised pork simmered for 45 mins were better than that of other simmering time.?2?Effects of the barrier properties of packaging materials on the quality of braised porkThree kinds of packaging materials with different barrier properties:polyester/aluminum/polyamide/high temperature polypropylene?abbreviated as H?,Si O₂ coated polyester/polyamide/high temperature polypropylene?abbreviated as M?,polyamide/high temperature polypropylene?abbreviated as L?were chosen to package braised pork and continuously tested the pork for its quality change under normal temperature storage to determine the shelf life of each group.Under the conditions of accelerated temperature simulation,the indexes of microorganism,moisture,sensory quality,and oxidation degree were measured every 3 months,and the flavor components were measured every 12 months.During storage,the three groups of samples were aseptically grown;the H group had the lowest decrease in L*,a*,b*values and moisture content,and the L group decreased significantly higher than the group H and M?P<0.05?;the three groups of samples Protein carbonyl value increased firstly and then decreased;thiobarbituric acid value?TBA?increased in all groups,group H was the slowest,group L was significantly higher than the other two treatment groups?P<0.05?.The electronic nose could clearly distinguish the volatile flavor components of each group.The three groups were mainly inorganic sulfides,nitrogen oxides,aromatic compounds and organic sulfides,alcohols;gas chromatography-mass spectrometry results showed that samples of three packaging materials in the storage process increased in volatile substances.Compared with the control,the concentration of compounds in groups H and M decreased during the early storage period and increased in the later period,and the concentration of volatile substances in group L has been increasing,which was significantly higher than the other two groups.Sensory evaluation results showed that the acceptable period of the three groups was:H 24 months,M 18 months,L 3 months.H is suitable for long-term storage of braised pork.?3?Effects of reheating methods on the quality of braised porkCompared with the control group,the L*of the braised pork in four reheating groups decreased;a*increased,b*decreased,and both the sensory score and the degree of oxidation increased.Opening bag self-heating and microwave are more helpful than closing bag self-heating and water bathing to improve the color of flexible package braised pork after reheating.The difference in the electronic nose and GCMS measurement results of the 4 reheat group braised meat samples failed to affect the human sensory score.The 4 reheat group samples had no significant difference in the sensory scores of taste,aroma and taste.They are appropriate reheating method for flexible packaging braised pork.