Kinetic Studies on the Effect of Salt on the Thermal Denaturation of Egg Constituents

Abstract

The aim of this study was to investigate the effects of salt on the kinetic parameters of thermal protein denaturation of egg constituents. Egg whites and yolks containing different quantities of added salt were analyzed using differential scanning calorimetry (DSC) and dynamic viscoelastic oscillatory measurements. DSC measurements revealed an increase in the denaturation temperatures of the second peaks of egg whites and yolks in the presence of elevated salt concentrations. Given that the activation energy values obtained from the kinetic analysis of egg proteins using dynamic DSC were comparable, we suggest that salt affects not the denaturation rate of the egg protein, but the temperature of denaturation. Dynamic viscoelastic oscillatory measurements revealed that the gel-point temperatures increased with increasing salt concentrations. The elevated gel-point temperatures coincided with the temperature of the maximum denaturation rate calculated using the kinetic parameters.