超声波辅助木瓜蛋白酶及发酵处理对牦牛肉的理化和质构特性

Effects of ultrasonic-assisted papain treatment and fermentation on physicochemical and texture change of yak meat

为探寻牦牛肉的嫩化方法,通过评价可溶性蛋白含量(content of soluble protein,CSP)、肌原纤维小片化指数(myofibril fragmentation index,MFI)、质构特性及蛋白质的降解,比较超声波、木瓜蛋白酶、超声辅助木瓜蛋白酶、发酵、超声辅助木瓜蛋白酶+发酵5种嫩化方法对牦牛肉嫩化效果的影响。结果表明,5种嫩化方法处理后牦牛肉的CSP范围为40.49~65.25 mg/g,均显著高于对照组(36.42 mg/g)(P<0.05),其中,超声辅助木瓜蛋白酶+发酵组的CSP最高,超声波处理组的CSP最低;5个处理组的MFI分别为85.73、97.13、110.60、65.07、69.00,显著高于对照组(P<0.05),且各个处理组间MFI差异显著(P<0.05);5种方法嫩化后牦牛肉的硬度、弹性、内聚性和咀嚼性均低于对照组(P<0.05),其中超声波辅助木瓜蛋白酶组最低;SDS-PAGE电泳图谱显示超声波辅助木瓜蛋白酶组和超声波辅助木瓜蛋白酶+发酵组对牦牛肉蛋白质降解的影响最为显著。

The objective of this study was to compare the tenderization effectiveness of treatments of ultrasound,papain,ultrasound-assisted papain,fermentation,or ultrasound-assisted papain with fermentation by evaluating the soluble protein content(CSP),myofibrillar fragmentation index(MFI),texture characteristics and protein degradation.Subsequent to each treatment,the CSP value of each method significantly increased(P<0.05).The CSP of the ultrasound-assisted papain with fermentation group had the highest CSP value,while the ultrasound-assisted group had the lowest.Also,the MFI significantly increased(P<0.05),while each treatment method produced significantly different(P<0.05)value.The hardness,springiness,cohesiveness,and chewiness of the yak meat tenderized by the five methods were lower than those of the control group(P<0.05).Among five groups,the ultrasound-assisted papain treatment method produced the lowest values.SDS-PAGE electrophoresis also showed that both the ultrasoundassisted papain treatment with and without fermentation method had the best tenderization effect.In summary,these results provide a theoretical basis for the tenderization of the yak meat and good reference for future product development.