Role of Protein in Reverse Osmosis of Cottage Cheese Whey

Proteins accumulated at the membrane surface during reverse osmosis of Cottage cheese whey. Gel filtration and gel electrophoresis indicated that the major component was casein, but a-lactalbumin and fl-lactoglobulin were also present. The acemnulation was in two forms--a gel-like deposit that resisted removal by fluid shear, and a viscous layer that was readily removed by flushing. The accumulated material reduced permeation rates. The accumulation was greatly reduced by increasing the flow velocity. The permeation rate data provided a basis for estimating the flow velocity at which formation of the protein layer is minimized.