Concentration of milk by ultrafiltration and reverse osmosis

Summary Whole milk from cows was concentrated 2-fold by reverse osmosis in a small pilot scale apparatus. All the main constituents of the milk were retained in the concentrate. The experiment showed that protein was a major cause of blocking of the membrane. Laboratory trials were therefore made on the ultrafiltration of milk to remove the protein with the aim of developing a 2-stage process for the concentration of milk by ultrafiltration followed by reverse osmosis with subsequent recombination of the concentrates from the 2 operations. The rates of both processes and the retentions of the constituents of milk by the membranes were measured.