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Beer Definitions

Having explained most of the following words at one time or another, I thought it might be useful if I set them all out here. The CAMRA website has a helpful article, About Real Ale, which explains much more about the distinctions involved, and about the process of brewing beer generally.

Words for Beer


An alcoholic drink made by extracting sugars and other chemicals from grain (usually malted barley) into water, and fermenting the resulting solution. The typical alcohol content ranges from 3% to 5%, with some beers as strong as 12%. Colours range from very pale yellow via reddish-brown to black.


Beer whose fermentation has been carried out at or near room temperature. This usually results in a vigorous primary fermentation, with the yeast typically collecting on the surface of the beer, hence the alternative adjective top-fermented. However, I believe there are some bottom-fermented ales. The category includes a very diverse range of beer styles.


Beer whose fermentation has been carried out near freezing. Compared to ale, this usually results in a much slower primary fermentation, with the yeast remaining at the bottom of the fermenting vessel, hence bottom-fermented. Lager is typically stored, again at low temperature, for at least several weeks during secondary fermentation; the word 'lager' is derived from the German for 'store' or 'storage'.

Real Ale

CAMRA originated the concept of "real ale", and have an official definition for it. From my perspective, the most important points are:

Contrary to a widely-held misconception, real ale is not warm. It is best served at about 55°F (13°C), i.e. somewhat below room temperature, much like red wine. Nor is real ale normally flat - it will usually have a light natural carbonation (from secondary fermentation in the cask).

Beer Vessels

Barrel (see below), cask and keg all have well-established general meanings; here I describe their use in the specific context of British brewing.


This is the generic name for the containers in which real ale is transported from the brewery to the pub, and from which it is served. There are various sizes, at least some of which are listed below. They are quite often referred to as barrels, but (in the context of brewing) this term should properly be reserved for the single specific size of cask.

Though casks are usually now made from metal rather than wood, they retain the traditional bowed sides. Casks have two holes: one in the side for ventilation (carbon dioxide out during fermentation, air in during serving), and one in the end, for the tap.


This is the generic name for the containers used for pasteurised beer, both ale and lager. In contrast to casks, kegs are usually straight-sided, and have only one hole, at one end: this accepts a specially-designed fitting, though which pressurised gas flows into the keg from one pipe, and beer flows out into another.

English Beer Measures

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Last update: 2008-03-28