Influence of calcium chloride addition on the properties of emulsions stabilized by whey protein concentrate

The properties of emulsions (30% soya oil) formed with 0.5 or 3.0% whey protein concentrate (WPC) and containing various concentrations of CaCl2 were investigated. In emulsions made with 0.5% WPC, addition of >3 mM CaCl2 before emulsification resulted in a large increase in average droplet diameter (d43) and a development of bimodal size distributions. The surface protein concentrations increased by ∼30% over that for the emulsion containing no added CaCl2. The creaming stability of these emulsions, measured after 24 h at 20°C, decreased gradually with increase in added CaCl2. In 3.0% WPC emulsions, addition of >10 mM CaCl2 resulted in a significant increase in d43 and surface protein concentration. The creaming stability of 3.0% WPC emulsions decreased markedly with addition of >15 mM CaCl2. Addition of CaCl2 to 0.5% WPC emulsions after they were made also resulted in increase in d43 and surface protein concentration and decrease in creaming stability. However, the stability of emulsions made with 3.0% WPC was not affected by the addition of CaCl2 after emulsification.