Ma Chao, Zhang Jian, Zhang Ruyu, Zhou Lei, Ni Laixue, Zhang Wangang
State Key Laboratory of Meat Quality Control and Cultured Meat Development, Ministry of Education China, Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
Food Chem X. 2024 Oct 21;24:101913. doi: 10.1016/j.fochx.2024.101913. eCollection 2024 Dec 30.
This work systematically investigated the effects of pre-slaughter transport stress on pork water holding capacity (WHC) during aging from the perspectives of oxidation, structure, function, and degradation properties of protein. Pigs were randomly divided into three-hour transport (Transport-induced stress, T group) and three-hour transport followed by three-hour resting (Control, TR group). Results demonstrated that T treatment markedly declined pork WHC. Compared with TR group, T group presented increased oxidation levels. Meanwhile, T treatment exacerbated the shift of protein secondary structure from α-helix to random coil and protein unfolding levels. The decreased solubility, thermal stability, and degraded levels of proteins were also observed in T group. Additionally, muscle contractions of T group were more severe than TR group. This study supported that pre-slaughter transport stress altered physicochemical properties and structures of postmortem muscle proteins, which reduced pork WHC via impairing the interactions between protein and water molecules and changing the muscle fiber structure.
本研究从蛋白质的氧化、结构、功能及降解特性等方面，系统地探究了宰前运输应激对猪肉成熟过程中持水力（WHC）的影响。将猪随机分为三组，分别为三小时运输组（运输诱导应激组，T组）和三小时运输后再休息三小时组（对照组，TR组）。结果表明，T处理显著降低了猪肉的WHC。与TR组相比，T组的氧化水平升高。同时，T处理加剧了蛋白质二级结构从α-螺旋向无规卷曲的转变以及蛋白质的展开程度。在T组中还观察到蛋白质的溶解度、热稳定性和降解水平降低。此外，T组的肌肉收缩比TR组更严重。本研究表明，宰前运输应激改变了宰后肌肉蛋白质的理化性质和结构，通过损害蛋白质与水分子之间的相互作用以及改变肌纤维结构，从而降低了猪肉的WHC。
