Influence of Acidity and Sodium Chloride on the Function Properties of Whey Protein Powder

The effectiveness of acidity and supplementation with different concentration of sodium chloride salt on function properties for whey protein powder prepared from salted and unsalted whey were investigated. The resultant whey protein powder was in a denatured form and contained about 50% protein. Whey protein powder from salted whey was generally more water soluble at any particular pH values (pH 2-7). There were no obvious differences between the two types of whey protein powder in their ability to diffuse to the water-oil interface (emulsifying oil in water). Moreover, little differences were observed between the two whey protein powder preparations in their ability for the formation of air dispersion in the liquid phase. Solubility index and foaming properties of whey protein prepared from unsalted whey increased by increased salt concentrations, while emulsifying capacity decreased by increased salt concentration until concentration 8% and dropped at concentration of 10% salt. It could be concluded that ionic strength has an important role in the functionality of whey protein concentrate.