The Research On Quality Changes Of Channel Catfish Seasoned Fish During Storage

Fish meat is rich in protein,fat,vitamins,and its nutritional value is high,but it is also easy to corrupt.How to prolong its shelf life and improve storage quality has always been an urgent problem to be solved.In this research,the channel catfish seasoned fish was used as the research object to study the quality changes of the fish under different storage temperatures and different freezing modes.The storage temperature was selected at-2℃,4℃and 10℃.The total number of colonies,p H,Total volatile basic nitrogen(TVB-N)and thiobarbituric acid(TBA)values,Centrifugal loss rate,K value of the seasoned fish were determined during storage,combined with sensory evaluation to explore the quality changes of seasoned fish under different storage temperatures.The results showed that the sensory scores of the seasoned fish decreased gradually with the storage time at the three storage temperatures.The p H and centrifugal loss rate decreased first and then increased,and the total number of colonies,TVB-N value,TBA value and K value showed an upward trend.According to various indicators,the seasoned fish stored at-2℃for micro-freezing storage had the best quality during storage,followed by the seasoned fish stored at 4℃,and the quality of fish stored at 10℃ decreased the fastest.-2℃,4℃ and 10℃ storage seasoned fish shelf life for 25 d,10 d and 6 d.The seasoned fish were slowly frozen(-18℃),moderately frozen(-30℃),and rapidly frozen(-80℃),and then transferred to-18℃ for storage.During storage,the p H,TVB-N value,TBA value,K value,and biogenic amine of the seasoned fish were measured,and combined with sensory evaluation,and measure the odor with electronic nose to explore the effects of different freezing methods on the quality of seasoned fish,the effects of different freezing methods on the quality of the seasoned fish were analyzed.The results showed that the p H of the three seasoned fish decreased first and then increased with the storage time during storage.The TVB-N value,TBA value,K value,putrescine and cadaverine increased with the storage time.The quality of slowly frozen seasoned fish was lower than that of the other two groups during storage.The sensory score at the end of storage was slightly lower than the acceptable score,and the cadaverine was detected at 56.9 mg/kg.The sensory scores of moderately frozen and rapidly frozen seasoned fish were not lower than the acceptable scores until the end of storage,but the moderately frozen seasoned fish detected cadaverine33.4mg/kg at the end of storage.The rapidly frozen fish did not detect cadaverine during the whole storage period,and the overall quality was good.The smell of the seasoned fish changed little in the moderately frozen and rapidly frozen,but changed more in the slowly frozen.Protein oxidation will seriously affect the storage quality of fish meat,extract the myofibrillar proteins of the seasoned fish in three kinds of frozen methods during storage,determine the oxidation index of myofibrillar proteins.The results showed that with the prolongation of storage time,the three kinds of treated seasoned fish myofibrillar proteins were oxidized to different degrees,which showed that the carbonyl content and surface hydrophobicity increased,and the active sulfhydryl groups,emulsifying properties and emulsion stability decreased.According to various indicators,the rapidly frozen seasoned fish protein has the lowest oxidation degree,and the slowly frozen seasoned fish protein has the most serious oxidation.