冷却猪肉新鲜度的色差快速分析评价方法

Rapid Analysis and Evaluation of Freshness of Chilled Pork Based on Color Difference

为了得到冷却猪肉新鲜度的变化规律,本研究以冷却猪肉里脊部分为研究对象,进行球蛋白沉淀实验、感官评价、pH值、水分含量、肉浸液以及肌肉表面颜色值测定。结果表明:球蛋白沉淀实验、pH值能够较好地反应肉品新鲜度的变化,色差分析符合一定的规律:肌肉表面色差测定中,20℃条件下,a*变化与贮藏时间显著相关(P<0.05),L*变化显著(P<0.05);4℃条件下,b*、C变化与贮藏时间极显著相关(P<0.01),L*值与pH值极显著相关(P<0.01);对于肉浸液,L*、b*、C、ΔE*均发生显著性变化(P<0.05),20℃条件下L*、b*、C、ΔE*与贮藏时间和pH值显著相关(P<0.05),而4℃条件下,L*、C、ΔE*与贮藏时间显著相关(P<0.05),L*、a*、b*、C、ΔE*值与pH值极显著相关(P<0.01);冷链过程中,当L*高于48.73、a*高于4.72、b*高于9.18时可认定冷却肉为新鲜肉。

The variability during storage under 4℃ and 20℃of chilled pork （longissimus dorsi muscle） was studied in globulin precipitation, sensory evaluation, pH, water content and the color and color parameters of pork surface and extract. The results indicated that the variations of globulin precipitation and pH in chilled had a significant difference. The color changes such as L＊ of pork surface under 20 ℃ and L^＊, b^＊, C and △E^＊ of pork extract differ significantly （P〈0.05）. The relationship between color changes and pH or storage time of chilled pork during storage was established. The CIE a^＊ under 20 ℃, b^＊ and C under 4℃ of pork surface as well as the L^＊, b^＊, C, and △E^＊ of pork extract under 20℃ and L^＊ under 4 ℃ were positively correlated with storage time. Moreover, the L^＊ of pork surface under 4℃, the L^＊, b^＊, C and △E^＊ of pork extract under both temperatures and a^＊ under 4 ~C were correlated positively with pH; when L^＊ 〉48.73, a^＊ 〉4.72 and b^＊ 〉9.18, chilled pork could be identified as fresh meat in cold chain.