Dairy wastewater utilization: separation of whey proteins in membrane and chromatographic processes

Dairies are obligated to utilize whey after cheese production. From an environmental protection point of view, the high content of lactose and proteins in post-production wastes, like whey, is harmful for the environment. From another point of view, whey is a source of very valuable, active proteins, particularly lactoferrin and serum albumin. Their modulatory potential is exhibited in their pure form and improves after partial, controlled hydrolysis. Unfortunately, the fractionation of this multicomponent medium is not an easy task. The paper describes an integrated process of fractionation of whey proteins. After the first step of treatment based on membrane techniques, the concentrated, most valuable whey proteins were subjected to a few steps of chromatographic separation. The separation properties of the ultrafiltration membranes were unexpected. The typical cut-off boundary was shifted in the direction of components having a lower molecular weight. After laboratory-scale testing, a concept for an industrial-scale process for the isolation of the most valuable whey proteins with purities of nearly 100% was elaborated.