Synergistic effects of plant polyphenols and metal ions on rabbit myofibrillar protein gel properties: Mechanisms and structural implications

Plant polyphenols, a class of plant-derived secondary metabolites with inherent antioxidant and antimicrobial activities, are widely utilized in meat product processing. However, current research on Plant polyphenols has primarily emphasized their intrinsic functional attributes, while the influence and mechanistic basis of their cooperative interactions with metal ions on the gelation behavior of rabbit myofibrillar protein (RMP) remain insufficiently clarified. This study systematically examined the effects of six Plant polyphenols and metal ions on the characteristics of heat-induced RMP gels. At 100 μmol/g, polyphenols markedly enhanced gel performance by inducing RMP conformational rearrangements and strengthening hydrophobic associations and hydrogen bonding, thereby generating a denser gel matrix and significantly increasing its hardness and water-holding capacity. The cooperative interactions between metal ions and Plant polyphenols vary with the ion type and concentration. Notably, 0.1 mol/L Mg 2+ synergistically increased gel strength by 26.7% when combined with resveratrol, whereas 0.1 mol/L Na + improved gel network stability. Additionally, 0.1 mol/L Al 3+ enhanced water retention by shielding the hydrophobic domains of the protein. In summary, the synergistic modulation of heat-induced RMP gels by Plant polyphenols and metal ions exhibited distinct concentration effects and ion-dependent specificity, effectively regulating gel architecture by altering protein conformation and intermolecular interactions.