Dealcoholization of beer.

Stein, W.

Abstract
The relative merits, with regard to both economics and product quality, of the principal methods of producing alcohol free and low alcohol beers are discussed. Methods covered include both altered fermentation techniques (removal of fermentable sugar from wort, low gravity brewing, curtailed fermentation, manipulation of yeast concentration using immobilized yeast, and the use of unusual yeast strains which cannot ferment the wort properly and thus produce little or no ethanol) and processes for the dealcoholization of normal beers (falling film evaporation, centrithermal evaporation, dialysis, reverse osmosis, pervaporation, alcohol absorption by molecular sieves and solvent extraction by supercritical carbon dioxide), some of which were still in the experimental stage at the time of writing and may not be suitable for commercial application. Measures to improve the flavour of the finished product include the brewing of a special flavour rich beer specifically for dealcoholization, the recovery and restoration to the beer of flavour volatiles from the alcoholic fraction after thermal separation, the production of a fuller flavoured low alcohol beer by blending an alcohol free beer with a beer of normal alcohol content, and the use of flavouring additives (in countries where this is permitted).
Keywords : alcohol free beer costs economics flavour low alcohol production quality survey