Studies On Quality And Protein Physical And Chemical Properties Of Carp Surimi Under Different Cold Storage Conditions

The squid is nutritious and easy to eat,and is loved by many people.However,the high moisture content of squid meat is highly prone to spoilage.The short shelf life limits the sales and circulation of fresh squid and its products.Therefore,finding effective preservation methods is of great significance for improving the economic benefits of carp culture and processing industry.Storage temperature is an important factor affecting the quality and shelf life of squid and its products.In this study,the squid was studied,and the fish carp was prepared by pre-treatment,meat collection,rinsing,dehydration and addition of freezing point regulator.(refrigerated),-2?(ice temperature),-4?(micro-frozen),-18?(freezing)four temperatures storage,at its sampling point to determine the p H value,volatile salts of carp surimi during storage The changes of base nitrogen,thiobarbituric acid value,color difference,cooking loss,texture,total number of bacteria,etc.,and sensory evaluation,to determine the quality characteristics and the best consumption period of the carp surimi under different storage temperatures.Furthermore,by measuring the changes of active sulfhydryl,total sulfhydryl,protein ATPase activity,surface hydrophobicity,emulsifying ability and solubility of carp fibrillary myofibrillar protein,the functional properties of carp surimi protein during storage were investigated.The research results are as follows:1.The sensory characteristics of the carp carp at different storage temperatures showed a downward trend.The squid carp in the second week had a sensory score <24(freshness),and the carp carp stored at the frozen temperature was around.The internal sensory score was always above 24 points,and the change was the slowest.The sensory score of the squid surimi stored at ice temperature was <24 points in the fifth week,and the sensory score of the squid squid in the micro-frozen storage was <24 points in the fourth week,but the squid squid in the first three weeks of ice temperature and micro-frozen storage Sensory scores were higher than frozen storage.Under different storage conditions,the texture characteristics of carp surimi were better than those of refrigerated and frozen under ice temperature andmicro-frozen storage.The texture of carp surimi was better than micro-frozen under ice-temperature storage,and the storage texture was poor under cold storage conditions.This is consistent with the sensory evaluation.The microbial growth and reproduction of the surimi under cold storage conditions is very fast,and corruption has begun to deteriorate in the third week.The fish gills under ice temperature and micro-freezing conditions can inhibit the growth of microorganisms compared with refrigerating,and the microbial growth is slow.The fish gills stored under the frozen storage conditions hardly grow during the eight-week storage period.With the increase of storage days,the TVB-N values of all groups showed an upward trend.The TVB-N value of the 4°C cold storage group increased rapidly,and the second week of storage was higher than 15mg/100 g,ice temperature and micro-frozen storage.The TVB-N value of the surrounding was higher than 15 mg/100 g,and the TVB-N value of the frozen storage of the carp surimi was less than 15 mg/100 g in eight weeks.Fresh salmon bream has a very low TBARS value of only 0.147 mg/kg.With the prolongation of storage time,the TBARS values of the four groups of samples showed an increasing trend.The higher the storage temperature,the faster the TBARS value increases.With the prolongation of storage time,the cooking loss rate of the frozen treatment group increased rapidly during the storage period,which was caused by the ice crystals inside the food causing certain damage to the tissue.The micro-frozen group also had a higher loss rate due to the formation of ice crystals inside the tissue,but it was less than the loss of the frozen group,and the cooking loss rate of the refrigeration and ice temperature storage was small.Combined with sensory characteristics,physical and chemical indicators and microbiological indicators,the best consumption period of refrigerated carp surimi is one week,the shelf life is 2 weeks,and the best consumption period of squid squid stored at ice temperature is four weeks,and the shelf life is five weeks.The best edible period for frozen storage of carp carp is three weeks,the shelf life is six weeks,the best edible period for frozen carp carp is four weeks,and the shelf life is more than eight weeks.The quality of frozen carp carp is four weeks after storage.decline.Compared with refrigerating,ice temperature and micro-frozen can effectively prolong the storage period of surimi;compared with freezing,the quality of ice temperature and micro-frozen surimi is better.2.Under different temperature storage conditions,the active sulfhydryl groups and total sulfhydryl groups in the carp surimi protein decreased,and the carbonyl group showed an upward trend.The temperature had a significant effect on the decline and the rise and fall.The lower the storage temperature,the slower the content of active sulfhydryl groups and total sulfhydryl groups decreases,and the faster the carbonyl content rises.The Ca2+-ATPase and K+-ATPase activities of the scorpion fibroblasts in the four control groups showed a downward trend overall,and the differences in ice temperature,micro-frozen and frozen storage temperatures were small,especially in the micro-frozen state and ice.There is very little difference in temperature status.Over time,the hydrophobicity of the surface of the protein increased.At three weeks,the surface hydrophobicity of the surimi protein stored at ice temperature was almost 1.8 times that of the fresh surimi.The effects of the four storage temperatures on the surface hydrophobicity of the protein are not much different.The emulsification of fresh surimi was 18.97 m2/g,and the emulsion stability was 98.48%.After a long period of storage,it decreased.Among them,the frozen fish gills fell the fastest,because the storage temperature was high,fat and protein oxidized quickly,and fell to 9.92 m2/g and80.33% in the second week.The ice temperature storage decreased the slowest,the emulsifying property decreased by 0.29% in four weeks,and the emulsion stability was only reduced by 0.08%.The emulsification and emulsion stability of frozen fish gills are not as good as ice temperature storage.Among the four storage methods,the solubility of frozen fish gizzard protein decreased relatively quickly,and the solubility of fish gill protein decreased sharply after four weeks of storage,and the solubility of surimi protein decreased under cold storage,ice temperature and micro-frozen storage.They are all slow.The decrease in protein solubility is consistent with an increase in carbonyl groups,a decrease in sulfhydryl content,and an increase in surface hydrophobicity.