真空预冷新鲜猪肉水分流失和DSC蛋白分析研究

Effect of vacuum cooling on water loss and DSC protein analysis of fresh pork

从汁液流失和蛋白变性来探讨真空预冷与传统的预冷方式和不同的真空预冷终温对新鲜猪肉的影响。结果表明,真空预冷后猪肉的失水率高于其它的预冷方式,且真空预冷终温越低,失水率也越高;真空预冷的降温速度是-18℃冷库预冷的1.5倍左右,是0℃冷库预冷的3倍;真空预冷过程中其箱体内相对湿度的变化先经历了快速降低,然后缓慢上升,再迅速上升三阶段。不同的预冷方式对峰Ⅰ、峰Ⅱ、峰Ⅲ的变性焓值存在着显著性差异(P<0.05)。真空预冷至4℃峰Ⅰ、峰Ⅱ的变性焓值相对于其它的预冷方式更接近于新鲜猪肉。

The influence of vacuum cooling and conventional cooling in fresh pork were discussed in this paper form water loss and protein denaturation. At the meantime, different vacuum cooling final tem- perature were discussed in order to determine the most suitable final temperature too. Comparing with the conventional cooling, the water loss of vacuum cooling was more higher. The more lower final tem- perature of vacuum cooling was, the more higher loss water would be. Comparing to the cooling rate of --18℃cold storage and 0℃ cold storage precooling,the vacuum cooling rate was more 1.5 times and 3 times respectively. The relative humidity curve of vacuum cooling chamber underwent three different stages, firstly, the curve had a quick down,secondly,the curve had a slow rise, and finally,the curve had a quick rise. Difference preeooling way had the significant difference（P〈0.05） in the denaturation enthalpy and temperature of peak Ⅰ ,Ⅱ , Ⅲ. However, the final temperature for 4℃ of vacuum cooling in denaturation enthalpy of peak Ⅰ ,Ⅱ got more close to the fresh pork than the other preeooling way .