Dihydromyricetin as a potential enhancer for surimi gels with anti-modori activity: A molecular docking and experimental validation

Modori is a major quality issue in surimi gels, and the development of safe and effective food ingredients to prevent this phenomenon is highly desirable. In this study, molecular docking was used to identify compounds that could bind to the predicted myofibril-bound serine proteinase (MBSP). Three compounds- Epigallocatechin gallate (EGCG), phytate, and dihydromyricetin (DMY)- were selected for investigation. The effects of these compounds on surimi gels containing 1.5% salt were studied, and a degradation analysis was conducted after incubation at 55 °C. Phytate did not inhibit the degradation of myosin heavy chain, whereas both EGCG and DMY promoted the formation of macromolecular aggregates associated with certain thermal stability. The addition of 0.4% of both polyphenols significantly improved the resistance of surimi gels to modori. However, when 3% salt was applied, EGCG displayed a primary promotion effect on gel deformation but reducecd breaking force. In contrast, DMY exhibited favorable impacts on breaking force, deformation, hardness, gumminess, and chewiness of resulting gels. Among the three covalent cross-linking bonds detected, Lys-DMY-Lys, Lys-DMY-Cys or Cys-DMY-Lys, and Cys-DMY-DMY-Cys, were formed between oxidized DMY and myofibrillar protein. DMY at 100 μM significantly inhibited the activity of MBSP, thus supporting the results obtained from the molecular docking study. Overall, these results suggest that dihydromyricetin is a better gel enhancer for surimi than other candidates tested. [Display omitted] •EGCG and DMY hindered the thermal degradation of MHC.•EGCG and DMY enhanced the resistance to modori of surimi gels.•DMY addition showed better effects on TPA, whiteness and WHC of surimi gels than EGCG.•100 μM DMY significantly inhibited MBSP activity.•DMY could interact with myofibrillar proteins through three kinds of covalent links.