See also: Fermentation in food processing § Brewing and winemakingīrewing has taken place since around the 6th millennium BC, and archaeological evidence suggests emerging civilizations including China, ancient Egypt, and Mesopotamia brewed beer. There are several additional brewing methods, such as Burtonisation, double dropping, and Yorkshire Square, as well as post-fermentation treatment such as filtering, and barrel-ageing. Fermentation may take place in an open or closed fermenting vessel a secondary fermentation may also occur in the cask or bottle. There are three main fermentation methods: warm, cool and spontaneous. Steps in the brewing process include malting, milling, mashing, lautering, boiling, fermenting, conditioning, filtering, and packaging. The most common starch source is ground cereal or 'grist' - the proportion of the starch or cereal ingredients in a beer recipe may be called grist, grain bill, or simply mash ingredients. Secondary sources ( adjuncts), such as maize (corn), rice, or sugar, may also be used, sometimes to reduce cost, or to add a feature, such as adding wheat to aid in retaining the foamy head of the beer.

Less widely used starch sources include millet, sorghum and cassava. Most beer is fermented with a brewer's yeast and flavoured with hops. The basic ingredients of beer are water and a fermentable starch source such as malted barley. Since the nineteenth century the brewing industry has been part of most western economies. Brewing has taken place since around the 6th millennium BC, and archaeological evidence suggests that emerging civilizations, including ancient Egypt, China, and Mesopotamia, brewed beer. It may be done in a brewery by a commercial brewer, at home by a homebrewer, or communally. See also: Brewing methods and Homebrewingīrewing is the production of beer by steeping a starch source (commonly cereal grains, the most popular of which is barley) in water and fermenting the resulting sweet liquid with yeast.

How to figure out mash tun dead space