Using Membranes to Purify Water and De-Alcoholise Beer

Abstract

Reverse osmosis is a membrane process which can be used both for purifying water and removing alcohol from beer.

The sharp selectivity of the latest thin-film composite membranes enables them to retain the molecules responsible for the characteristic flavour, colour and aroma of beer, while allowing alcohol and water molecules to permeate through. “Diafiltration water” must be added continually to the beer during de-alcoholisation to maintain its normal composition.

This paper describes a case-history in which the use of reverse osmosis — both to de-alcoholise beer and purify the diafiltration water — resulted in substantial benefits for the brewery in terms of product quality, costs and plant operation.