Beer



A beer is any variety of alcoholic beverages produced by the fermentation of starchy material derived from grains or other plant sources. The production of beer and some other alcoholic beverages is often called brewing. Historically, beer was known to the Sumerians, Egyptians, and Mesopotamians, and dates back at least as far as 4,000 BC. Because the ingredients used to make beer differ from place to place, beer characteristics (type, taste, and colour) vary widely.

Ingredients

Typically, beers are made from water, malted barley, hops, and fermented by yeast. The addition of other flavourings or sources of sugar is not uncommon.

Because beer is composed mainly of water, the source of the water and its characteristics have an important effect on the character of the beer. Many beer styles were influenced or even determined by the characteristics of the water in the region.

Among malts, barley malt is the most often and widely used owing to its high enzyme content (which facilitates the breakdown of the starch into sugars) but other malted and unmalted grains are widely used, including wheat, rice, maize, oats, and rye.

Hops are a comparatively recent addition to beer (see History below). They contribute a bitterness that balances the sweetness of the malt and have a mild antibiotic effect that favours the activity of brewer's yeast over less desirable organisms. Enzymes in yeast, in a process called fermentation, metabolize the sugars extracted from the grains, producing many compounds including alcohol and carbon dioxide. Dozens of strains of natural or cultured yeasts are used by brewers, roughly sorted into three kinds: ale or top-fermenting, lager or bottom fermenting, and wild yeasts. Top-fermenting means that the yeast ferments in the top of the fermenting vessel. Conversely, bottom-fermenting means that the yeast ferments in the bottom of the fermenting vessel. The scientific name for ale yeast is Saccharomyces cerevisiae, an important model organism in molecular and cell biology; Saccharomyces carlsbergensis is the scientific name for lager yeast.

During the process of filtration (also called fining or clearing), some brewers add agents to beer that are not required to be published as ingredients. Since these finings may include animal extracts, vegans and others concerned with the use or consumption of animal products may wish to contact the brewer for specific details of the filtration process. Isinglass finings are a common animal-derived clarifying agent, extracted from fish. Alternatively, Irish moss is a commonly used plant-based clarifying agent.

One pint of beer typically contains about two to three units of alcohol, although alcohol content can vary significantly with style and brewer.

History

Almost any sugar or starch-containing food can naturally undergo fermentation, and so it is likely that beer-like beverages were independently invented in cultures throughout the world. In Mesopotamia, the oldest evidence of beer is on a 6000-year old Sumerian tablet which shows people drinking a beverage through reed straws from a communal bowl. Beer is also mentioned in the Epic of Gilgamesh, and a 3900-year old Sumerian poem honoring the brewing goddess Ninkasi contains the oldest surviving beer recipe, describing the production of beer from barley via bread. Beer became vital to all the grain-growing civilizations of classical antiquity, especially in Egypt and Mesopotamia.

Beer was important to early Romans, but during Republican times wine displaced beer as the preferred alcoholic beverage, and beer became considered a beverage fit only for barbarians. Tacitus wrote disparagingly of the beer brewed by the Germanic peoples of his day.

Most beers until relatively recent times were what we would now call ales. Lagers were discovered by accident in the sixteenth century when beer was stored in cool caverns for long periods; they have since largely outpaced ales in volume. (See below for the distinction.) The use of hops for bittering and preservation is a medieval addition. Hops were cultivated in France as early as the 800s. The oldest surviving written record of the use of hops in beer is in 1067 by Abbess Hildegard of Bingen: "If one intends to make beer from oats, it is prepared with hops." In 15th century England, an unhopped beer would have been known as an ale, while the use of hops would make it a beer. Hopped beer was imported to England (from the Netherlands) as early as 1400 in Winchester and hops were being planted on the island by 1428. The Brewers Company of London went so far as to state "no hops, herbs, or other like thing be put into any ale or liquore wherof ale shall be made ? but only liquor (water), malt, and yeast." However, by the 16th century, "ale" had come to refer to any strong beer, and all ale and beer were hopped.

Methods of brewing changed very little from that time. In 1953, New Zealander Morton W Coutts developed the technique of continuous fermentation which was the first major change to brewing since the 16th century. Morton patented his process which revolutionized the industry by reducing a four-month long brewing process to less than 24 hours [1] (http://www.roadshow.org/html/resources/scientists/coutts/article.html). His process is still used by many of the world?s major breweries today, including Guinness.

In 1516, the duchy of Bavaria adopted the Reinheitsgebot, perhaps the oldest food regulation still being used. The Reinheitsgebot ordered that the ingredients of beer be restricted to water, barley, and hops. The law soon spread throughout Germany, and has since been updated to reflect modern trends in beer brewing. To this day, the Reinheitsgebot is (controversially) considered a mark of purity in beers.

Etymology

Of the two terms, ale is the elder in English. It comes directly from the proto-Indo European root *alu-, through Germanic *aluth-[2] (http://www.bartleby.com/61/roots/IE14.html). Beer, on the other hand, is considered to come from the Latin bibere (to drink)[3] (http://www.bartleby.com/61/69/B0156900.html). Old English sources distinguish between "ale" and "beer" but do not define what was meant by "beer" during that period, although there is some speculation that it refers to what would now be called cider (alcoholic form). The Old English form of "beer" disappeared shortly after the Norman Conquest, and the word re-entered English centuries later, in exclusive reference to hopped malt beverages.

In Slavic languages, beer is called "pivo", from the verb "piti" ? to drink. So, "pivo" could be translated to English as "the drink".

Mythology

The Kalevala, collected in written form in the 19th century but based on oral traditions many centuries old, contains more lines about the origin of brewing than are devoted to the origin of man.

Lager

Lagers are probably the most common type of beer consumed. They are of Central European origin, taking their name from the German lagern ("to store"). Bottom-fermented, they were traditionally stored at a low temperature for weeks or months, clearing, acquiring mellowness, and becoming charged with carbon dioxide. Modern methodological methods of producing lager were pioneered by Gabriel Sedlmayr II (who perfected dark brown lagers at the Spaten brewery in Bavaria) and Anton Dreher (who began brewing a lager, probably of amber-red color, in Vienna in 1840-1841). The first golden lager was produced in the Bohemian town of Pilsen in 1842. These days, with improved fermentation control, most lager breweries use only short periods of cold storage (1?3 weeks).

Ale

Top-fermented beers, particularly popular in the British Isles, include mild, bitter, pale ale, porter, and stout. Top-fermented beers tend to be more flavoursome, including a variety of grain flavours and fermentation flavours; they have also lower carbonation and are fermented and ideally served at a higher temperature than lager. Stylistic differences among top-fermented beers are decidedly more varied than those found among bottom-fermented beers and many beer styles are difficult to categorize. California Common beer, for example, is produced using a lager yeast at ale temperatures. Wheat beers are often produced using an ale yeast and then lagered, sometimes with a lager yeast. Lambics employ wild yeasts and bacteria, naturally-occurring in the Payottenland region of Belgium. Other examples of ale include stock ale, old ale, and Belgian-style ale. Real ale is a term for beers produced using traditional methods, and without