Han Seokhee, Jo Kyung, Jeong Seul-Ki-Chan, Jeon Hayeon, Kim Soeun, Woo Minkyung, Jung Samooel, Lee Seonmin
Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, Korea.
Food Sci Anim Resour. 2024 Sep;44(5):1055-1068. doi: 10.5851/kosfa.2024.e37. Epub 2024 Sep 1.
The differences in the proteolytic patterns and shear force of pork and beef during aging were evaluated. Pork and beef muscles were obtained at 24 and 48 h postmortem, respectively, and aged at 4°C for 0 (Day 0), 7 (Day 7), and 14 days (Day 14). Changes in the electrical conductivity were observed in pork on Day 7 and beef on Day 14. The calpain activity increased in pork (p<0.05) after 14 days of aging, whereas that of beef decreased on Day 7 (p<0.05). The cathepsin B activity in pork and beef increased between Day 7 and 14 (p<0.05). The content of α-amino group in the 10% trichloroacetic acid-soluble fraction increased between Day 7 and 14 in pork (p<0.05), but increased steadily in beef throughout aging (p<0.05). The electrophoretogram of the myofibrillar proteins revealed a 30 kDa protein band only in the beef lane on Day 14. The cooked pork had no significant changes in the shear force during aging periods (p>0.05), while the gradual decrease in the shear force with the increasing aging periods was shown in the cooked beef (p<0.05). Circular dichroism analysis of myosin extracts from pork and beef revealed thermal denaturation temperatures of 55°C and 58°C, respectively. This study highlights the different post-mortem proteolytic patterns and thermal denaturation temperatures of myosin in pork and beef muscles, which contribute to distinct changes in the shear force during aging between pork and beef.
评估了猪肉和牛肉在成熟过程中蛋白水解模式和剪切力的差异。分别在宰后24小时和48小时获取猪肉和牛肉肌肉，并在4℃下成熟0天（第0天）、7天（第7天）和14天（第14天）。在第7天的猪肉和第14天的牛肉中观察到电导率的变化。猪肉在成熟14天后钙蛋白酶活性增加（p<0.05），而牛肉在第7天降低（p<0.05）。猪肉和牛肉中的组织蛋白酶B活性在第7天至第14天之间增加（p<0.05）。猪肉中10%三氯乙酸可溶性部分的α-氨基含量在第7天至第14天之间增加（p<0.05），但牛肉在整个成熟过程中稳步增加（p<0.05）。肌原纤维蛋白的电泳图谱显示，仅在第14天的牛肉泳道中有一条30 kDa的蛋白带。在成熟期间，熟猪肉的剪切力没有显著变化（p>0.05），而熟牛肉的剪切力随着成熟时间的增加而逐渐降低（p<0.05）。对猪肉和牛肉的肌球蛋白提取物进行圆二色性分析，结果显示热变性温度分别为55℃和58℃。本研究突出了猪肉和牛肉肌肉中宰后蛋白水解模式和肌球蛋白热变性温度的差异，这导致了猪肉和牛肉在成熟过程中剪切力的明显变化。
