Effect of superfine grinding on the structural and physicochemical properties of whey protein and applications for microparticulated proteins

Effects of superfine grinding on structural and physicochemical properties of whey protein concentrate (WPC) and applications for microparticulated whey protein (MWP) were investigated. WPC and MWP particle sizes significantly (p < 0.05) decreased after superfine grinding from 62 and 15 A mu m to 15 and 9 A mu m, respectively, compared with controls. A basis for exploration of WPC applications as a fat replacer because of WPC and MWP particle size reductions due to superfine grinding is established. The effect of superfine grinding on molecular configuration, thermal stability, and physicochemical properties of WPC were also investigated. Amounts of free sulfhydryl groups decreased significantly (p < 0.05) from 18.16 to 14.49 A mu mol/L, and thermodynamic properties, including transition temperature, were changed after superfine grinding. The whey protein solubility, protein surface hydrophobicity, oil binding capacity, foaming capacity, and foaming stability of WPC were all improved after superfine grinding.