Abstract: The effects of different concentrations of H2O2 on the degree of oxidation and gelation properties of myofibrillar proteins were studied, and we also examined changes in the secondary structure and spatial structure of myofibrillar protein gels after H2O2 oxidation. The results showed that hydroxyl radicals derived from H2O2 could promote the oxidation of myofibrillar proteins, and that the degree of oxidation increased with increasing H2O2 concentration. The gelation properties of myofibrillar proteins regularly changed with the degree of oxidation. The gel strength, water retention, storage modulus and loss modulus decreased, whereas the surface hydrophobicity showed an increasing trend. Furthermore, the secondary structures of α-helix and β -sheet were partially destroyed and became unstable as H2O2 concentration increased. By observing the network structure of the protein gels by scanning electron microscopy, it was confirmed that protein oxidation hindered protein gels from forming a spatial structure.

Key words: myofibril protein, protein oxidation, gel properties, secondary structure, spatial structure