Isolation of lactoferrin and immunoglobulins from dairy whey by an electrodialysis with filtration membrane process

•Fabrication of asymmetric PVA filtration membranes for lactoferrin(LF) separation.•The separation of LF from other major proteins is achieved by its aggregation in a salty buffer.•Electrodialysis with filtration used to obtain a whey protein retentate rich in Ig and LF.•Tradeoff between protein removal rate and energy consumption. Isolation of high value minor proteins such as lactoferrin and immunoglobulins from crude dairy streams is a major challenge for the dairy industry. Here we investigate an electrodialysis with filtration membrane (EDFM) approach to separate lactoferrin (LF) and immunoglobulins (Ig) from other dairy proteins. A polyvinyl alcohol (PVA) membrane is prepared using phase inversion in a coagulation bath with 80% ethanol to serve as the filtration membrane. A range of treatment times and two electric field strengths (38.5 and 77 V/cm) were then investigated within the electrical cell. The results show that the filtration membrane prepared in-house can offer strong rejection for LF and Ig while allowing a high flux of other proteins. The separation of LF and Ig from a simulated whey solution can be achieved. The use of a partially demineralised whey reduces protein loss, but there is a tradeoff between the energy consumption and the protein removal rate as the extent of this demineralisation is increased.