The terms “alcohol-free” and “low-alcohol” beer are often used interchangeably. While these differences in terminology can cause some confusion, the discrepancy is easily explained: legally, any beer that contains up to 0.5% alcohol by volume (ABV) counts as “alcohol-free”. This small amount of leeway allows for trace amounts of alcohol, which is difficult to eradicate entirely when using typical brewing methods. 

If you’re a regular or occasional drinker of alcohol-free beer, it’s likely that you’ve asked the question, how is it made? Is the alcohol removed or is alcohol-free beer produced a different way?

There are currently four main methods of producing alcohol-free beer: 

1. Dealcoholisation: This method involves brewing an alcoholic beer and then removing the alcohol afterwards. It is a mode of production that is typically practiced by industrial brewers as it requires expensive equipment and better suits large-scale production. Dealcoholisation can be done in several different ways: boiling or vacuum distillation. Boiling is the more basic of the two methods and simply involves steaming off the alcohol from the beer. Vacuum distillation modifies the steamingprocess: sealing the beer in a vacuum enables it to boil at a lower temperature, which reduces the risk of high heats damaging the beer. 

Another way to dealcoholize beer is through reverse osmosis. This is the most technical of these processes. The beer is filtered through a membrane that catches the large flavour molecules while letting the smaller alcohol molecules pass through.

2. Dilution: Here the beer is made in the same way as an alcoholic beer, but this time it is diluted with water until only a residual amount of alcohol (0.5% ABV) remains. 

3. Restricting fermentation: This is the method favoured by smaller independent brewers. One of the ways to limit the production of alcohol is to use ingredients that contain fewer fermentable sugars than those used in conventional beer. There are also strains of yeast that contain fewer sugars. 

A second method of restricting fermentation is to deactivate the yeast before it starts to produce high-volume alcohol. This is done by reducing the temperature of the beer to near freezing point while it is fermenting. 

4. Eliminating fermentation: By eliminating fermentation altogether, brewers are able to produce beer that is free from trace amounts of alcohol. To do this, the wort (the liquid that forms the base of the beer) is not inoculated with yeast. 

Alcohol-free beer is an expanding market, which has been eagerly embraced by independent brewers as well as much bigger macro breweries. At Brew Cavern and Brew Tavern, we maintain a permanent selection of the best offerings from independents from around the UK. Some of our favourite breweries making alcohol-free beers include: We Can Be Friends, Track, and Mash Gang.