Cheese whey was chemically pretreated and subjected to one of nine semi-pilot scale, physical pretreatment modifications involving various combinations of centrifugal clarification (CC) and/or microfiltration (MF) to remove residual lipids and phospholipoprotein complexes. Two pretreatment modifications were most effective for producing whey with least turbidity and lowest lipid and phosphoIipid contents. Whey given these two pretreatments provided highest ultrfiltration (UF) membrane flux rate and upon drying of the UF retentate resulted in the most highly functional WPCs in terms of solubility, foam expansion, emulsifying activity and gelation.