Permeate

Permeate is a by-product of the dairy industry, primarily produced during the manufacture of cheese and whey protein. It is essentially a liquid mixture of lactose, minerals, and water, derived from whey. The process involves filtering whey to remove most of the protein and fat, leaving behind a concentrated solution of lactose and minerals.

Manufacturers add permeate to foods as a source of lactose, which can act as a sweetener and contribute to browning reactions (Maillard reaction) during cooking. It is often used in baked goods, confectionery, and processed dairy products like cheesecakes and ice cream, as well as in some savoury snacks such as crisps, to enhance flavour and texture.

Permeate is not classified as a food additive in the UK and therefore does not have an E-number. It is primarily composed of lactose, a natural sugar found in milk. As a source of lactose, its consumption contributes to overall sugar intake. The UK's dietary advice, as outlined by SACN and the Eatwell Guide, recommends that free sugars should not exceed 5% of total dietary energy. While permeate itself has not been specifically evaluated by bodies like EFSA for safety as an additive, its components are well-understood.