Milk whey protein recuperation by coacervation with polysaccharide

Abstract

This work aimed to recover and fractionate milk whey proteins through the coacervation technique, using sodium carboxymethyl cellulose (CMC) polysaccharide. Milk whey was obtained from the manufactured cheese type "frescal". Polymer concentration (0.1-0.9% CMC w/v) and pH values were studied in order to obtain a selective precipitation of whey proteins; conditions were optimized to pilot scale production. After pH gradual adjustment the precipitation of total proteins (PT/CMC) was achieved for pH 3; for pH 4 b-lactoglobulin (b-Lg/CMC) precipitation and for pH 3.2 the greatest proportion of a-lactoalbumin (a-La/CMC) precipitation. Coacervates were separated by centrifuge force, and characterized in relation to their composition and electrophoretic profile. The highest yield was obtained from fractionation of b-Lg/CMC with precipitation of 86% of this whey protein type. Highest protein content was showed by b-Lg/CMC, probably due to the proportion among hydrocolloids. The a-La/CMC showed minor protein content and yield recuperation of this whey protein fraction.