Beer
Beer is the world's most widely consumed and likely the oldest alcoholic beverage; it is the third most popular drink overall, after water and tea. The production of beer is called brewing, which involves the fermentation of starches, mainly derived from cereal grains--most commonly malted barley, although wheat, maize (corn), and rice are widely used. Most beer is flavoured with hops, which add bitterness and act as a natural preservative, though other flavourings such as herbs or fruit may occasionally be included. The fermentation process causes a natural carbonation effect which is often removed during processing, and replaced with forced carbonation. Some of humanity's earliest known writings refer to the production and distribution of beer: the Code of Hammurabi included laws regulating beer and beer parlours, and "The Hymn to Ninkasi", a prayer to the Mesopotamian goddess of beer, served as both a prayer and as a method of remembering the recipe for beer in a culture with few literate people.
What brewing process naturally carbonates beer?
fermentation
The fermentation process causes a natural carbonation effect which is often removed during processing, and replaced with forced carbonation.
beer