干燥温度对风干牛肉贮藏期间品质及蛋白质降解的影响

为研究干燥温度对风干牛肉贮藏期品质及蛋白质降解的影响,本研究以新疆褐牛后腿肉为原料,采用不同干燥温度对脉动压力腌制后的牛肉进行干燥(30℃,50 h;40℃,20 h;50℃,12 h;60℃,8 h)、冷却、真空包装后,置于-4℃冰箱中贮藏(0、3、6、9、15、21 d),研究干燥温度对风干牛肉贮藏期间品质及蛋白质降解情况的影响。结果表明,随着贮藏时间的延长,不同温度下水分含量逐渐减少(p<0.05);蒸煮损失率先增大后逐渐减小,然后再逐渐增大;不同干燥温度下,水分含量和蒸煮损失率均为30℃>40℃>50℃>60℃;贮藏末期50℃干燥的牛肉气味、口感和总体可接受性最高,60℃口感、滋味和总体接受性最低(p>0.05);弹性在整个贮藏期内变化不显著(p>0.05)。肌原纤维蛋白羰基含量显著增加(p<0.05),其中干燥温度为60℃时,增加趋势最大;总巯基含量显著减少(p<0.05),其中干燥温度为60℃时,减少趋势最大;十二烷基硫酸钠聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)结果表明,30、40、50℃的风干牛肉肌原纤维蛋白条带在贮藏第15 d降解作用增强,而60℃的蛋白质在第9 d降解作用增强。综上,干燥温度为50℃时,蛋白质的降解程度较低,能更好地保持风干牛肉整个贮藏期的品质。

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.