低温贮藏对川式腊肉中蛋白质降解的影响

Effect of different ways of low temperature storage on the protein degradation in Sichuan-style bacon

新鲜腊肉采用直接真空包装(A处理)和添加抗坏血酸后真空包装(B处理)后,分别在5℃和-18℃下贮藏,探讨蛋白质的降解和氨基酸组成变化。结果表明,各处理水分含量随贮藏时间的延长逐渐下降,氨基酸组成分析显示,各处理中必需氨基酸相对含量均呈增加趋势。冷藏120d时A、B处理E/N比从初始值0.65分别升至结束时的0.75和0.73,AAS从13.06分别升至44.57和51.23;冻藏处理E/N比和AAS呈先升后降趋势,冻藏120d时A、B处理E/N比从初始值0.65分别升至0.71和0.90,而AAS从13.06分别升至31.16和31.86。各处理挥发性盐基氮随贮藏时间延长不断增加,但符合SB/T10294-1998中规定二级品≤45mg/100g,超出分割冻猪肉国标、鲜、冻四分体带骨牛肉国标15mg/100g。表明短期低温贮藏和添加抗坏血酸可改善腊肉氨基酸组成,不影响腊肉食用品质。

The cured-meat was divided into A group and B group （adding ascorbic acid） and packed by vacuum treatment separately. Then respectively were stored in the refrigeration storage （5℃） and in the frozen storage （-18℃）,then discussed the change of protein degradation and amino acid composition in different storage time. The result showed that the content of water and protein decline gradually during the storage time,adding ascorbic acid might delay protein degradation in the refrigeration temperature. The analysis about amino acid composition implied that the relative contents of essential amino acid in all groups were increasing in the storage time. In 120d in the refrigeration storage,the E/N ratio in both A and B groups increased from 0.65 to 0.75 and 0.73 in the end respectively,AAS raised from 13.06 to 44.57 and 51.23 separately while the E/ N ratio and AAS increased at the first and then declined in the end in the frozen storage,the E/N ratio came up from 0.65 to 0.71 and 0.90,AAS climbed from 13.06 to 31.16 and 31.86. During the whole refrigeration and frozen storage,the content of volatile nitrogen was uptrend,this meet the standard of SB/T 10294-1998 that middlings≤45mg/100g,but still in excess of national standard of segmentation of frozen pork and frozen beef （15mg/100g）. All of the results showed that to keep the Sichuan-bacon in a low temperature in a short time and add the ascorbic acid may change the composition of protein and amino acid in a good way and have no bad effects on quality of eating.