Effect of Resveratrol on Gel Properties of Silver Carp Myofibrillar Protein

The effects of different concentrations (0.05%, 0.1%, 0.15%, 0.2%, and 0.25%) of resveratrol (RE) on the structural properties, rheological properties and gel properties (gel strength, water retention, water mobility, whiteness and microstructure) of silver fish myofibrillar protein were investigated. RE was found to combine with myofibrillar protein molecules, resulting in an increase in the particle size. Ultraviolet (UV) absorption spectra and intrinsic fluorescence spectra showed that the addition of RE changed the spatial conformation of myofibrillar protein and reduce its fluorescence intensity. The rheological results showed that the addition of RE increased the storage modulus and loss modulus of myofibrillar protein. As the amount of added RE increased, the gel strength first increased and then decreased. The addition of 0.15% of RE increased it by 38.43% compared with the control group. In addition, the addition of RE also improved the texture properties of the gel and increased the whiteness. Low-field nuclear magnetic resonance (LF-NMR) analysis showed that the addition of RE transformed part of the free water into immobilized water, enhancing the water-binding capacity of the gel. Scanning electron microscopy (SEM) showed that the addition of RE promoted the formation of a denser gel network. These results show that when added at an appropriate level, RE could interact with silver carp myofibrillar protein to change its conformation, thereby enhancing the gel properties of myofibrillar protein and forming a dense gel network structure. The results of this study can provide a reference for improving the gel properties of freshwater fish surimi and the quality of surimi products.