Effects of the Addition of Whey Protein Concentrates on the Water-retention Properties and Texture of Ham

Abstract

By alteration of pH values and addition of salts and sugar during the process of ham preparation, the denaturation temperatures of whey protein concentrates (WPC) and their constituents, α-lactalbumin (α-La) and β-lactoglobulin (β-Lg) were investigated by differential scanning calorimetry (DSC). The denaturation temperatures of WPC, α-La, and β-Lg shifted to the higher temperature by alteration of pH values to an isoelectric value for each protein, and addition of sodium chloride. These results may due to alteration of the balance of forces (such as charge-charge interactions, hydrophobic bonding, and hydrogen bonds etc.) which have been implicated in the stabilization of the secondary-tertiary structure of a globular protein according to the change of pH values or addition of sodium chloride. Secondly, effects of the addition of WPC on model hams preparation were studied. The DSC curves of the model ham paste added WPC showed another endothermic peak besides the endothermic peaks that were found in the model ham paste without WPC. From these results, it became evident that WPC, a-La, and β-Lg denaturated at the heating temperature (ca.75°C) in ham preparation process. The ability of water-retention was improved and some properties, such as strength, cohesiveness, elasticity and chewyness, became higher in the ham added WPC.