Abstract: This invention relates to a process for the recovery of .alpha.-lactalbumin and/or .beta.-lactoglobulin enriched whey protein concentrate from a whey protein product. The process comprises the following steps:a) incubating a solution comprising whey protein product with a calcium-binding ionic exchange resin in its acid form to initiate the instabilization of .alpha.-lactalbumin,b) adjusting the pH of the treated protein product solution to a value between 4.3 and 4.8, after separation of the resin,c) incubating the protein product solution at a temperature between 10 and 50.degree. C. to promote the flocculation of .alpha.-lactalbumin,d) fractionating the proteins in the protein product solution at pH 4.3-4.8, providing an .alpha.-lactalbumin enriched fraction and a .beta.-lactoglobulin enriched fraction,e) raising the pH of the .alpha.-lactalbumin enriched fraction sufficiently to solubilize the .alpha.-lactalbumin fraction, andf) optionally raising the pH of the .beta.