莱芜猪肌肉胶原蛋白的发育性变化及其与肉质的相关性分析

 【目的】探讨肉质特性的构成实质和调控机制，为地方猪种的选育和利用提供依据。【方法】以30～90 kg体重莱芜猪和40～100 kg体重鲁莱黑猪共84头去势公猪为试验对象（每组6头），研究肌肉中胶原蛋白含量和性质（交联度）的发育性变化及其与肉质特性的关系。【结果】莱芜猪肌肉总胶原蛋白含量（TC）、不溶性胶原蛋白含量（IC）和胶原蛋白的溶解度（CS）以及肉质特性的大理石纹（MS）和剪切值（SF）在不同体重组间存在显著（P＜0.05）或极显著（P＜0.01）的差异。鲁莱黑猪肌肉中TC、IC、CS和可溶性胶原蛋白含量（SC）以及肉质特性的MS、熟肉率（CP）和拿破率（NY）在不同体重组间存在显著（P＜0.05）或极显著（P＜0.01）的差异。研究的两个品种猪肌肉中胶原蛋白的发育性变化基本一致，随体重的增长，肌肉中TC和IC逐渐增加，而SC和CS的总体趋势逐渐下降；肌肉MS、持水性能（WBC）是逐渐增大，肌肉嫩度则逐渐下降。与鲁莱黑猪相比，莱芜猪肌肉胶原蛋白含量较多且其溶解度也较高，而且具有较高的肌肉MS、WBC和较低的SF。【结论】胶原结缔组织能够在肌肉、肌束乃至每根肌纤维表面以原纤维网的形式形成膜鞘结构，肌肉胶原蛋白含量的增加及其溶解度的下降，能够改善肌肉的持水性能，但同时也降低肌肉的嫩度（P＜0.01）。肌肉大理石纹含量的增加则能够在不影响肌肉嫩度（P＞0.05）的情况下显著改善肌肉的持水性能（P＜0.05）。

Study on the Development Changes of Intramuscular Collagen and Their Relationship to Meat Quality in Laiwu Pig

Eighty-four Laiwu Black (LW) (weight of 30-90kg, n=6) and Lulai Black (LL) pigs (weight of 40-100kg, n=6) were used to study the development changes of intramuscular collagen and their relationship to meat quality. The results showed as follows: Weight of LW had significant effects on muscle total collagen (TC), insoluble collagen (IC) (P<0.01), collagen solubility (CS) (P<0.05), marbling score (MS) (P<0.01) and shear force (SF) (P<0.05). Weight of LL had significant effects on muscle TC, soluble collagen (SC) (P<0.05), IC, CS, MS (P<0.01), cooking percentage (CP) and Napole yield (NY) (P<0.05). These two breeds, on the whole, had similar development changes of intramuscular collagen. Increased weight of pigs was associated with an increase in muscle TC, IC and water binding capacity (WBC), but tended to be related with a decrease in muscle SC, CS and tenderness. Compared with LL, LW were generally higher in muscle TC, CS, MS and WBC, but lower in SF. It was proved that as the whole muscle, bundles of fibers and individual fibers are surrounded by a delicate collagenous network like sheaths, the increase of quantity of collagen and its cross-links was found to be highly correlated to muscle WBC improvement and toughness (P<0.01), whereas, the increase of amounts of marbling was strongly correlated to WBC improvement (P<0.05) but not to toughness.