Effect of partial substitution of NaCl by KCl , CaCl 2 , and MgCl 2 on properties of mixed gelation from myofibrillar protein and Flammulina velutipes protein

Abstract

The effects of substitution of sodium chloride (NaCl) by chloride salt mixtures (KCl, CaCl2, and MgCl2) with different formulas on quality characteristics of mixed protein system containing 80% myofibrillar protein (MP) and 20% Flammulina velutipes protein (FVP) were investigated in this study. The addition of chloride salts (KCl, CaCl2, and MgCl2) into a reduced-sodium (0.3 M NaCl) mixed gel system, increased the gel properties, and network structure of the MP-FVP gel, which might be attributed to the increase in protein solubility and rheological properties. The examination of the turbidity, particle size, zeta potential, UV spectroscopy, and Fourier transform infrared spectroscopy indicated that the protein molecules were obviously aggregated, that the electrostatic interaction was weakened, that the hydrophobic interaction and β-sheet content was increased. The results showed that when KCl, CaCl2, and MgCl2 were used to replace NaCl at 35, 10, and 5%, respectively, the gel properties reached the maximum. Practical applications This study evaluated the effects of different types of sodium salt substitution on the structural properties of proteins and the structural properties of mixed myofibrillar protein and Flammulina velutipes protein gels. The results revealed that the mixed protein molecules apparently aggregated under different replacement of KCl, CaCl2, and MgCl2 (i.e., 35, 10, and 5%). The hydrophobicity and β-sheet content significantly increased, while the electrostatic interaction decreased, leading to enhanced mixed gel properties. The results indicated the different replacements of sodium salts could improve the gels characteristics, which may be a guide for the future production of low-salt meat products.