Effects of calcium chloride and licorice flavonoids on Tan sheep myofibrillar protein oxidation and gelation: Synergistic impact of endogenous characteristic active substances

Abstract

To investigate the effects of the synergistic interaction between calcium chloride (CaCl₂) and licorice flavonoids (LF) on the structural changes, oxidation, gel properties, water content, and intermolecular interactions of sheep myofibrillar protein (MP), an in vitro MP model was used. Protein structure and sulfhydryl content indicated that with the addition of CaCl₂ and LF, MP initially unfolds under the influence of CaCl₂, then oxidizes, followed by an increase in α-helix content, reflecting enhanced structural order. Molecular docking and low-field nuclear magnetic resonance revealed that CaCl₂ and LF primarily bind to MP via hydrophobic interactions, hydrogen bonds, forming complexes. When LF is added at 0.32 mg/100 g and CaCl₂ at 120 mg/100 g, the gel structures exhibit optimal stability (P < 0.05). In conclusion, the synergistic interaction between LF and CaCl₂ enhances the unique characteristics of sheep meat by balancing the unfolding, oxidation, and crosslinking of MP, offering a natural additive for better meat products.