The cross‐linking effects and action mechanism of epigallocatechin gallate (EGCG) on myofibrillar protein from common carp (Cyprinus carpio) were investigated. According to particle size, zeta potential, and atomic force microscopy, EGCG could cause the aggregation of myofibrillar protein, while hydrogen bonds and electrostatic interactions were the main molecular forces. With the measurement of Fourier transform infrared spectrum, surface hydrophobicity, fluorescence spectrum, circular dichroism spectrum, and molecular dynamics simulation, EGCG could make the spatial configuration of myofibrillar protein loose, enhance the exposure of amino acid residues, and further change its secondary and tertiary structures by forming intermolecular and intramolecular hydrogen bonds with myofibrillar protein. In addition, the gel properties of myofibrillar protein were improved by EGCG. All results suggested that EGCG had the cross‐linking effects on myofibrillar protein in carp meat and could further improve its properties, which showed the potential to improve the qualities of fish meat in food industry. Practical applications Compared with other meat, fish meat is particularly easy to break and deteriorate during its processing and sales due to the short length and low cross‐linking degree of fish myofibrillar protein, which shows some negative impacts on the quality of fish meat. In the present study, epigallocatechin gallate (EGCG) showed the significant cross‐linking effects on carp myofibrillar protein and further improved its physicochemical properties. All results suggested that EGCG had the potential to increase the cross‐linking degree of fish myofibrillar protein and improve its properties, so as to ameliorate the quality of fish meat during processing and storage.

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In this research, the effects and action mechanism of tea polyphenols (TP) on the quality of common carp meat during the freezing process were investigated. During the freezing process, TP could reduce the thawing loss of carp meat and improve its texture properties. Moreover, TP showed the remarkable capability to inhibit protein denaturation and enhance the thermal stability of the myofibrillar protein (MP) in carp meat. In addition, by the observation of fluorescence spectrum and Fourier transform‐infrared spectrum, the tertiary and secondary structures of MP could be obviously changed with the treatment of TP. Furthermore, according to the analysis of molecular docking, TP could interact tightly with MP by hydrogen bonds and hydrophobic interactions, which changed the spatial structure of MP and affected the quality of carp meat. All present results suggested that TP had a potential value to improve the quality of common carp meat during the freezing process. In the present study, TP could reduce the thawing loss of carp meat and improve its texture properties during the freezing process by interacting with carp's MP. All results suggest that TP have the potential to improve the quality of common carp meat during the freezing process. Novelty impact statement In present study, tea polyphenols could reduce the thawing loss of carp meat and improve its texture properties during freezing process by interacting with carp's myofibrillar protein. All results suggest that tea polyphenols have the potential to improve the quality of common carp meat during freezing process.