Beer has been a staple of African, Mediterranean and European diets since ancient times. It was likely discovered in ancient Egypt or Mesopotamia and predates written history. In its simplest form, beer is a cloudy alcoholic beverage made (or "brewed") from fermented grain.
Beer in Period
Beer was a staple drink for all social classes. It was cheap, easy to make, and safer than water, since the alcohol killed the bacteria and parasites common in water. Period beer was about four- or five-percent alcohol by volume, at a minimum, although a much weaker form known as small beer was also commonly consumed. Small beer has an alcoholic content of only one- or two-percent, and was a staple beverage for both adults and children.
Hops are the ubiquitous flavouring, bittering and preserving agent in modern beer. While hops have been used in some beers since antiquity, cultivation of hops for brewing is generally considered to have become widespread in the 13th_century. Various bittering herbs and plants were used previously for similar results. (See also: Wikipedia's entry on beer.)
Modern beer may include a variety of ingredients in addition to malt and hops. These may include additional flavourings, such as spices, orange peel and herbs, adjuncts such as corn, rice, and sugar, and clarifying agents such as isinglass, Irish moss, carageenan, gelatin and egg white.
The strength of modern beer varies greatly, from as little as 3% for some English mild ales to over 12% for Tripels and other strong ales. Alcohol content is often driven by excise taxes, rather than style considerations. For example, Victoria Bitter ("VB"), was recently reduced from 4.9% to 4.8% alcohol content to save the brewer around A$20 million per year.