An investigation of the fractionation of whey proteins by two microfiltration membranes with nominal pore size of 0.1 micro m.

摘要

There is growing interest in the fractionation of whey proteins because of the specific properties of individual whey proteins. The objective of this work was to assess the efficiency of two membranes to obtain two fractions, one rich in beta -lactoglobulin ( beta -Lg) and the other rich in alpha -lactalbumin ( alpha -La) from a whey-protein concentrate using microfiltration (MF). Two MF membranes were tested for the fractionation: a flat-sheet membrane VCWP and a spiral membrane MF-7002, both with nominal pore sizes of 0.1 micro m. The VCWP retained 78% of the proteins in solution, and this membrane was shown to be permeable to both proteins, beta -Lg and alpha -La. The retention of protein by MF-7002 was 65%, and there was a partial retention of lactose. The permeate collected in the MF-7002 in the concentration stage was over 50% alpha -La; although this was present in lower concentrations, it was passed preferentially to the permeate. The results indicated that some aggregation of the proteins may have occurred under the experimental conditions because there was only a partial separation of the proteins under study.