Protein Degradation And Quality Analysis Of Different Parts Of Yanbian Yellow Beef During Storage

There were many factors that affected the beef quality, carcass splitting parts after slaughter, the structure and functional characteristics of the proteins in muscle had significant effect on the quality of meat and meat products.There were a series of biochemical changes during the beef storage which would change the structure and composition of proteins, the tenderness, water holding capacity, texture and flavor of the beef and also have an impact on the safety of meat and meat products.Therefore to perfect the Yanbian yellow beef quality evaluation system, strengthen the knowledge about the mechanism of Yanbian yellow beef quality changes, provided guidance to design a reasonable process and parameters while developing new meat products, the protein degradation of tenderloin, huxin meat, breast meat of Yanbian yellow beef carcass splitting parts were contrasted, and the quality diversity were analyzed.1. Protein degradation in different parts of Yanbian yellow beef during storageThe protein degradation in different parts of Yanbian yellow beef during storage were studied, the protein hydrolysis indexes, protein solubility were determined, the correlation of protein degradation related indicators were analyzed and the changes of different molecular weight proteins were analyzed by SDS-PAGE in this experiment. The results were as follows:There were significant changes of TN, NPN and PI in different parts of Yanbian yellow beef during storage at P<0.05 and parts had significant effects on protein hydrolysis of beef at P<0.05. Relatively, PI of tenderloin was lower, because its TN content was high while NPN content was low. Oppositely, PI of breast meat was higher because its TN content was low while NPN content was high. Those showed that the protein hydrolysis of breast meat was higher than that of tenderloin and huxin meat. In terms of protein solubility, total protein solubility and myofibrillar protein solubility of huxin meat were higher, sacoplasma protein solubility of breast meat was higher than that of tenderloin and huxin meat during storage. Storage time and parts had significant effects on protein solubility at P< 0.05. There was correlation between the protein degradation related indexes of Yanbian yellow beef during storage, but there were some differences of the correlation of each indicator between the different parts. It indicated the interaction of each index, rather than a single change. the protein degradation related indexes in different parts of Yanbian yellow beef were positively correlated with storage time, while the PI of breast meat was negatively correlated with storage time. The results of SDS-PAGE showed that the content of total protein, sacoplasma protein and myofibrilla protein in the three parts of beef were different and had varying degradation during storage, the changes of protein in different parts of the beef were different. Three kinds of protein in tenderloin and breast meat changed greatly, multiple different molecular weight protein changed with the extension of storage time, total protein in huxin meat changed obviously while sacoplasma protein and myofibrillar protein relatively stabilized.2. Quality variance in different parts of Yanbian yellow beef during storageTo get variation and diversity by comparing and analyzing, quality variance in different parts of Yanbian yellow beef during storage were studied in this experiment, the general nutrional component, processing characteristics indexes and storage quality indexes during storage were determined. The results were as follows:General nutrional component content in the different parts of the yanbian yellow were significant different at P<0.05. The crude protein content of the breast meat was 21.08% and crude ash content was 1.14% which were both higher than the other two parts at P<0.05. The crude fat content in huxin meat was 11.88% which was significantly higher than the other two parts while the other nutrional component indexes were significantly lower than the other two parts at P<0.05. The water holding capability in tenderloin was better, its meat was tender and had stable spring and better processing characteristics. In contrast, the water holding capability and processing characteristics in breast meat were poorer and its meat was coarser and harder. Freshness of tenderloin was higher than the other two parts, and its color was brighter. Freshness of the three parts beef during storage was tenderloin> huxin meat >breast meat. Storage time and parts had significant effects on freshness at P<0.05.