Maple CDE Practice Test 2026 – The All-in-One Guide to Master Your Certification Exam!

Membrane separation uses two streams: permeate and concentrate. Permeate is the water that passes through the semipermeable membrane, while the concentrate (retentate) contains the remaining solutes. In maple sap processed by reverse osmosis, water moves through the membrane into the permeate stream, so the water removed from the sap is called permeate. The sugars and minerals stay behind, forming the concentrate. Filtrate is a term from filtration processes, and condensate is vapor that has condensed, which aren’t the standard labels for RO output. So the water removed by the reverse osmosis machine is permeate.