Changes in Gelation Properties of Silver Carp Myosin Treated by Combination of High Intensity Ultrasound and NaCl

The molecular behavior of myosin in a low-salt environment limited the production of surimi-based products. This study aimed to investigate the effect of the combination of high intensity ultrasound (HIU) and NaCl (0.1, 0.3, 0.5 mol/L) on the physicochemical indexes of myosin. The changes were evaluated by solubility, ultraviolet (UV) spectroscopy, dynamic rheological properties, water holding capacity (WHC), microstructures, etc. For control samples, the gelation properties of myosin strengthened upon NaCl increasing. Combination of HIU and NaCl significantly improved the solubility of myosin, which was due to the conformational changes and the exposure of reactive groups. Meanwhile, the particle size of myosin obviously decreased when observed by atomic force microscope, which in turn promoted the stability of myosin. Furthermore, the improvement in solution behaviors of myosin treated by combination of HIU and NaCl contributed to the gelation properties as well as the formation of compact microstructures, which obtained high WHC and low cooking loss of myosin gels. In conclusion, combination of HIU and NaCl induced the unfolding of myosin with the exposure of reactive groups, consequently facilitating the formation of denser microstructures. Moreover, the biggest degree of improvement in gelation properties was observed at 0.1 mol/L NaCl combined with HIU.