The influence of pH and monovalent/divalent cations on the structural and physicochemical properties of myofibrillar protein from silver carp

The present study aimed to investigate effects of pH and monovalent (Na+ and K+)/divalent (Ca2+ and Mg2+) cations on the structural and physicochemical properties of myofibrillar protein (MP) from silver carp. MP treated with divalent cation had lesser change for the structure than that treated with monovalent cation. Ca2+-ATPase activity of MP treated with monovalent cation was increased firstly and then decreased, while that treated with divalent cation was decreased with increasing ionic strength. Surface hydrophobicity and Z-average of MP treated with divalent cations was lower than that with monovalent cations, while they decreased and then increased with the pH shifting from 3.0 to 9.0. Zeta potential of MP was increased and then decreased with increasing the pH but decreased and then increased with increasing ionic strength. In general, the pH and monovalent/divalent cations could cause various hydrophobic and electrostatic interactions, resulting in changes of the physicochemical properties of MP.