Membranes have become important tools in food processing, permitting ultrafiltration, microfiltration, and reverse osmosis with selective polymer membranes. The goal may be concentration, clarification, or fractionation.
Membranes differ in their apparent pore size, their affinity for dissolved and suspended matter, their materials of construction, their costs, and their durability. Early reverse osmosis membranes were made of cellulose acetate, valued for its ability to reject dissolved salt an…