Abstract:Objective To explore the effects of sodium chloride (NaCl) on the functional and structural properties of porcine plasma proteins (PPP), with the aim of providing a reference for the practical application of PPP.Methods PPP was treated with different concentrations of NaCl (0~1.0 mol/L), and changes in its functional and structural properties were measured using ultraviolet-visible spectrophotometry, laser particle size analysis, and Zeta potential analysis.Results NaCl promoted the solubility of PPP, reaching a peak at 0.2 mol/L. With further increases in NaCl concentration, solubility showed a downward trend. The trends in surface hydrophobicity and emulsifying properties of PPP changed at 0.8 mol/L, with maximum increases of 69.75% and 23.88%, respectively. NaCl had a negative effect on the foaming ability of PPP, as evidenced by a reduction in foam formation. In addition, compared with the control, the water-holding capacity of PPP decreased, with a maximum reduction of 40.18%, while the oil-holding capacity and turbidity increased, with maximum increases of 50.22% and 37.93%, respectively. In terms of structural characteristics, the UV absorption spectrum of PPP exhibited a blue shift, the average particle size increased, and both the absolute value of Zeta potential and the free sulfhydryl content decreased. These findings indicate that NaCl facilitated intermolecular interactions among PPP molecules, thereby altering their structural properties.Conclusion NaCl can enhance intermolecular interactions among PPP molecules, leading to changes in protein structure and thus regulating their functional properties.