Effect of Drying Temperature on Quality and Protein Degradation of Dried Beef During Storage

In order to study the influence of drying temperature on quality and protein degradation during storage of air-dried beef,the beef of Xinjiang was used as the raw material and was dried at different drying temperatures(30℃,50 h;40℃,20 h;50℃,12 h;60℃,8 h),cooled,vacuum packaged,and then preserved in refrigerator at -4℃(0,3,6,9,15,21 d)to study the effects of drying temperature on quality protein degradation. The results showed that,with the prolongation of storage time,the moisture content at different temperatures gradually decreased(p<0.05);the cooking loss rate increased first and then decreased gradually,and then gradually increased;and at different drying temperatures,the water content and cooking loss rate both were 30℃>40℃>50℃>60℃(p<0.05);At the end of storage,dried beef samples at 50℃ had the highest odor,mouthfeel,and overall acceptability;60℃ had the lowest taste,flavor and overall receptivity(p>0.05);elasticity did not change significantly during the entire storage period(p>0.05). The carbonyl content of myofibrillar protein was significantly increased(p<0.05)with the trend of maximum increase at 60℃;the total sulfhydryl content was significantly decreased(p<0.05),among which the decreasing trend was greatest at 60℃. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)showed that the degradation of myofibrillar protein bands at 30,40,50℃enhanced on the 15th day of storage,while the protein degradation was enhanced at 60℃ on the 9th day. To sum up,when the drying temperature was 50℃,the degradation degree of protein was lower,which could better maintain the quality of air-dried beef in the whole storage period of air-dried beef.