Protective effect of porcine plasma protein hydrolysates on the gelation of porcine myofibrillar protein exposed to a hydroxyl radical-generating system

This study investigated the effect of different concentrations of porcine plasma protein hydrolysates (PPPH) on the gelation of porcine myofibrillar protein (MP) exposed to a hydroxyl radical-generating system (HRGS). Compared to non-oxidized MP, the oxidative modification led to a decreased penetration force and water holding capacity (WHC) (P < 0.05). Meanwhile, addition of PPPH (1.5 mg/mL) reduced the loss of MP gel strength and WHC induced by HRGS (P < 0.05). Low-field nuclear magnetic resonance results suggested that the addition of PPPH facilitated the hydration of the protein. The results concerning molecular forces revealed that hydrophobic interactions, hydrogen bonds, and disulphide bonds are the primary forces in gel formation. Non-reducing electrophoresis indicated that the addition of PPPH reduced protein loss and aggregation. The addition of PPPH promoted the formation of a more smooth and homogeneous gel network. Our results demonstrated that PPPH effectively retarded oxidation-induced MP gel deterioration and could be used as an antioxidant in meat products.