The mechanism of improved myosin gel properties by low dose rosmarinic acid addition during gel formation

In this study, the interaction mechanism between rosmarinic acid (RA) and myosin and its effect on gel formation during the heating process at different NaCl concentrations were investigated. The results showed that the RA addition improved the strength, water retention and elastic modulus of myosin gel. During the gel formation, the head aggregation of myosin was weakened due to the enhanced hydrophobic interaction and hydrogen bonds between RA and myosin. As temperature increased, the partially oxidized RA could form covalent crosslinking with the sulfhydryl groups of myosin. The interaction between RA and myosin promoted the unfolding of myosin structure, resulting in the reduction of the α-helix content and the exposure of hydrophobic groups of myosin, which accelerated the gel formation of myosin during the heating process. Moreover, the medium-high NaCl concentration facilitated these non-covalent and covalent interactions, thereby improving the gel properties of myosin.