[Phase equilibria in water-defatted milk proteins-carboxymethylcellulose sodium salt systems]

Phase equilibria in water mixtures of skimmed milk with sodium salt of carboxymethylcellulose (CMC) was studied using two degrees of CMC polymerization (500 and 200) and substitution (0.8 and 0.5). The increase of the polymerization degree from 200 to 500 resulted in a higher protein yield in the protein phase, while the decrease of the substitution degree from 0.8 to 0.5 caused a noticeable decrease of asymmetry of phase diagrams. The phase separation was accompanied by ion exchange: potassium and calcium ions were mainly found in the protein phase. The highest yield of milk protein into the protein phase was 85% at a CMC concentration of 0.7%. The main protein component of the polysaccharide phase was alpha-lactalbumin.