Characterization of physicochemical properties of casein mixture preparation extracted from organic milk for use as an emulsifier in organic processed foods

Abstract

BACKGROUND Sodium caseinate (SC) is not considered suitable for use as an emulsifier in organic processed food in the food industry because of the use of prohibited synthetic chemical substances during its production. Casein mixture preparation (CMP), one of the permissible substances specified in the regulations, was isolated from organic milk using citric acid and dibasic potassium phosphate for organic processed foods. RESULTS To compare CMP and SC, model emulsions stabilized with each substance were prepared at various concentrations and their physicochemical properties were analyzed. The emulsions' stability was determined using Turbiscan under various environmental stresses. The zeta potential of SC and CPM showed a high surface charge (<= 30 mV) at all protein concentrations. Because the concentration of the protein preparation increased to 0.75% (w/v), the particle size of the CMP emulsion decreased with the surface load increased as much as that of SC. The CMP and SC emulsions were stable at neutral pH and room temperature. However, at acidic pH and high temperature, both emulsions were destabilized by creaming and flocculation and increased the creaming migration rates. CONCLUSION Overall, our data suggest the use of CMP as an emulsifier substitute for SC in organic processed foods. (c) 2018 Society of Chemical Industry