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beer
This article is about the beverage; for other meanings see beer (disambiguation).

A selection of bottled beers
A selection of cask beersBeer is the world's oldest and most popular alcoholic beverage. It is produced through the fermentation of starch-based material, commonly cereal, though cassava root in Africa, potato in Brazil, and agave in Mexico, among other starch sources, have been used.

Only beverages produced by this method are considered to be beer. Neither alcoholic beverages made from the fermentation of sugars derived from non-starch sources (e.g., grape juice or honey), nor beverages which are distilled after fermentation should be classified as such.

Because the ingredients and procedures used to make beer can differ, characteristics such as taste and colour may also vary. While local names for beers made with the same methods and ingredients may vary, the similarities of method and ingredients can be detected to form a study of the nature of beer styles.

History

Egyptian woman making beer (Cairo Museum)Main article: History of beer
Beer is one of the oldest beverages humans have produced, dating back to at least the 5th millennium BC (prior even to writing), and recorded in the written history of Ancient Egypt and Mesopotamia. As almost any substance containing carbohydrates, namely sugar or starch, can naturally undergo fermentation, it is likely that beer-like beverages were independently invented among various cultures throughout the world.

Beer largely remained a homemaker's activity, made in the home in medieval times. By the 14th and 15th centuries, beermaking was gradually changing from a family-oriented activity to an artisan one, with pubs and monasteries brewing their own beer for mass consumption.

Today, the brewing industry is a huge global business, consisting of several multinational companies, and many thousands of smaller producers ranging from brewpubs to regional breweries.

The brewing process
For a full explanation see Brewing
Though the process of brewing beer is complex and varies considerably, the basic stages that are consistent are outlined below. There may be additional filtration steps between stages.

Mashing: The first phase of brewing, in which the malted grains are crushed and soaked in warm water in order to create a malt extract. The mash is held at constant temperature long enough for enzymes to convert starches into fermentable sugars.
Sparging: Water is filtered through the mash to dissolve the sugars. The darker, sugar-heavy liquid is called the wort.
Boiling: The wort is boiled along with any remaining ingredients (excluding yeast), to remove excess water and kill any microorganisms. The hops (whole, pelleted, or extract) are added at some stage during the boil.
Fermentation: The yeast is added (or "pitched") and the beer is left to ferment. After primary fermentation, the beer may be allowed a second fermentation, which allows further settling of yeast and other particulate matter "trub" which may have been introduced earlier in the process. Some brewers may skip the secondary fermentation and simply filter off the yeast.
Packaging: At this point, the beer contains alcohol, but not much carbon dioxide. The brewer has a few options to increase carbon dioxide levels. The most common approach by large-scale brewers is force carbonation, via the direct addition of CO2 gas to the keg or bottle. Smaller-scale or more classically-minded brewers will add extra ("priming") sugar or a small amount of newly fermenting wort ("kräusen") to the final vessel, resulting in a short refermentation known as "cask-" or "bottle conditioning".
After brewing, the beer is usually a finished product. At this point the beer is kegged, casked, bottled, or canned.

Unfiltered beers may be stored for further fermentation in conditioning tanks, casks or bottles to allow smoothing of harsh alcohol notes, integration of heavy hop flavours, and/or the introduction of oxidised notes such as wine or sherry flavours. Some beer enthusiasts consider a long conditioning period attractive for various strong beers such as Barley wines. There are some beer cafes in Europe, such as Kulminator in Antwerp, which stock beers aged ten years or more. Aged beers such as Bass Kings Ale from 1902, Courage Imperial Russian Stout and Thomas Hardys Ale are particularly valued.

Ingredients

Malted barley before roastingMain articles: Hops, Saccharomyces cerevisiae, Brewer's yeast, Malt and Barley
The basic ingredients of beer are water, a fermentable starch source, such as malted barley, and yeast. It is common for a flavouring to be added, the most popular being hops. A mixture of starch sources may be used, with the secondary starch source, such as corn, rice and sugar, often being termed an adjunct, especially when used as a lower cost substitute for malted barley.

Water: Beer is composed mainly of water, which when heated is known as brewing liquor. The characteristics of the water have an influence on the character of the beer. Although the effect of, and interactions between, various dissolved minerals in brewing water is complex, as a general rule, hard water is more suited to dark beer such as stout, while very soft water is more suited for brewing pale ale and pale lager.

Starch source: The most common starch source is malted cereal. And among malts, barley malt is the most widely used owing to its high amylase content, a digestive enzyme which facilitates the breakdown of the starch into sugars. However, depending on what can be cultivated locally, other malted and unmalted grains may be used, including wheat, rice, oats, and rye, and less frequently, maize and sorghum. Malt is formed from grain by soaking it in water, allowing it to start to germinate, and then drying the germinated grain in a kiln. Malting the grain produces the enzymes that will eventually convert the starches in the grain into fermentable sugars. Different roasting times and temperatures are used to produce different colours of malt from the same grain. Darker malts will produce darker beers. Two or more types of malt may be combined.

Crushed hopsFlavourings: Hops have commonly been used as a bittering agent in beer since the seventeenth century. Hops contain several characteristics very favourable to beer: (a) hops contribute a bitterness that balances the sweetness of the malt, (b) hops also contribute aromas which range from flowery to citrus to herbal, (c) hops have an antibiotic effect that favours the activity of brewer's yeast over less desirable microorganisms and (d) the use of hops aids in "head retention", the length of time that a foamy head created by the beer's carbonation agent will last. The bitterness of commercially-brewed beers is measured on the International Bitterness Units scale. While hop plants are grown by farmers all around the world in many different varieties, there is no major commercial use for hops other than in beer.

Yeast: is a microorganism that is responsible for fermentation. A specific strain of yeast is chosen depending on the type of beer being produced, the two main strains being ale yeast (Saccharomyces cerevisiae) and lager yeast (Saccharomyces uvarum), with some other variations available, such as brettanomyces and Torulaspora delbrueckii. Yeast will metabolise the sugars extracted from the grains, and produce alcohol and carbon dioxide as a result. Before yeast's functions were understood, fermentations were conducted naturally using wild or airborne yeasts; although a few styles such as lambics still rely on this ancient method, most modern fermentations are conducted using pure yeast cultures.

Clarifying agent: Some brewers add one or more clarifying agents to beer that are not required to be published as ingredients. Common examples of these include Isinglass finings, obtained from swimbladders of fish; kappa carrageenan, derived from seaweed; Irish moss, a type of red alga; and gelatin. Since these ingredients may be derived from animals, those concerned with the use or consumption of animal products should obtain specific details of the filtration process from the brewer.

Varieties of beer
Main article: Beer style
Though there are only a few distinct types of beer, there are many different names and style labels that attempt to categorise beers by overall flavour and, occasionally, origin. The British beer writer Michael Jackson wrote about beers from around the world in his 1977 book The World Guide To Beer and organised them into local style groups based on local information. This book had an influence on craft and home brewers in United States who developed an intricate system of categorising beers which is exemplified by the Beer Judge Certification Program. Outside of North America beer is mainly categorised by strength and/or colour.

Yeast

Main article: Brewer's yeast
A common method of categorising beer is by the behaviour of the yeast used in the fermentation process. In this method of categorising, those beers which use a fast acting yeast which leaves behind residual sugars are termed ales, while those beers which use a slower and longer acting yeast which removes most of the sugars leaving a clean and dry beer are termed lagers.

Ale

Main article: Ale

Cask alesA modern ale is commonly defined by the strain of yeast used and the fermenting temperature.

An ale yeast is normally considered to be a top-fermenting yeast, though a number of British brewers, such as Fullers and Weltons, use ale yeast strains that settle at the bottom. Common features of ale yeasts regardless of top or bottom fermentation is that they ferment more quickly than lager yeasts, they convert less of the sugar into alcohol (giving a sweeter, fuller body) and they produce more esters (which give a fruity taste) and diacetyl (which gives a buttery taste).

Ale is typically fermented at higher temperatures than lager beer (15–23°C, 60–75°F). Ale yeasts at these temperatures produce significant amounts of esters and other secondary flavor and aroma products, and the result is a beer with slightly "fruity" compounds resembling but not limited to apple, pear, pineapple, banana, plum, or prune.

Stylistic differences between some ales and lagers can be difficult to categorize. Steam beer, Kölsch and some modern British Golden Summer Beers are seen as hybrids, using elements of both lager and ale production. Baltic Porter and Bière de Garde may be produced by either lager or ale methods or a combination of both. However, commonly, lager is perceived to be cleaner tasting, dryer and lighter in the mouth than ale.

Lager

Main article: Lager

A glass of lagerLagers are the most commonly-consumed beer in the world. They are of Central European origin, taking their name from the German lagern ("to store"). Lager yeast is a bottom-fermenting yeast, and typically undergoes primary fermentation at 7-12°C (45-55°F) (the "fermentation phase"), and then is given a long secondary fermentation at 0-4°C (30-40°F) (the "lagering phase"). During the secondary stage, the lager clears and mellows. The cooler conditions also inhibit the natural production of esters and other byproducts, resulting in a "crisper" tasting beer.

Modern methods of producing lager were pioneered by Gabriel Sedlmayr the Younger, 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. With modern improved fermentation control, most lager breweries use only short periods of cold storage, typically 1–3 weeks.

Spontaneous fermentation

Main article: Lambic
These are beers which use wild yeasts, rather than cultivated ones. All beers before the cultivation of yeast in the 19th century were closer to this style, characterised by their sour flavours.

Colour

Main article: Pale ale
Another common method of categorising beer is by colour. The colour of a beer is determined by the malt. The most common colour is a pale amber produced from using pale malts. Pale ale is a term used for beers made from malt dried with coke. Coke had been first used for roasting malt in 1642, but it wasn't until around 1703 that the term pale ale was first used. In terms of volume, most of today's beer is based on the pale lager brewed in 1842 in the town of Plzen, in the Czech Republic. The modern Pilsner lager is light in colour and high in carbonation, with a strong hop flavour and an alcohol by volume content of around 5%. The Pilsner Urquell and Heineken brands of beer are typical examples of pale lager, as are the American brands Budweiser, Coors, and Miller.

Very dark beers , such as stout, use very dark malts.

Draught and keg beers

Draught beer keg fonts at the Delirium Café in BrusselsMain articles: Draught beer, Widget (beer) and Keg beer
Draught beer from a pressurised keg is the most common dispense method in bars around the world. A metal keg is pressurised with carbon dioxide (CO2) gas which drives the beer to the dispensing tap or faucet. Some beers, notably stouts, such as Guinness and "Smooth" bitters, such as Boddingtons, may be served with a nitrogen/carbon dioxide mixture. Nitrogen has fine bubbles, producing a dense head and a creamy mouthfeel.

In the 1980s Guinness introduced the beer widget, a nitrogen pressurised ball inside a can which creates a foamy head. The words "draft" and "draught" are often used as marketing terms to describe canned or bottled beers containing a beer widget.

Cask ales

Schlenkerla Rauchbier direct from the caskMain article: Cask ale
Cask ales are unfiltered and unpasteurised. When the landlord feels the beer has settled, and he is ready to serve it, he will knock a soft spile into a bunghole on the side of the cask. The major difference in appearance between a keg and a cask is the bunghole. A keg does not have a bunghole on the side.

The soft spile in the bunghole allows gas to vent off. This can be seen by the bubbles foaming around the spile. The landlord will periodically check the bubbles by wiping the spile clean and then watching to see how fast the bubbles reform. There still has to be some life in the beer otherwise it will taste flat, but too much life and the beer will taste hard or fizzy. When the beer is judged to be ready, the landlord will replace the soft spile with a hard one (which doesn’t allow air in or gas out) and let the beer settle for 24 hours. He will also knock a tap into the end of the cask. This might simply be a tap if the cask is stored behind the bar. The beer will then be served simply under gravity pressure: turn on the tap, and the beer comes out. But if the cask is in the cellar, the beer needs to travel via tubes, or beer lines, up to the bar area using a beer engine.

Bottle conditioned beers
Main article: Bottle conditioning
Bottle conditioned beers are unfiltered and unpasteurised. It is usually recommended that the beer is poured slowly, leaving any yeast sediment at the bottom of the bottle. However, some drinkers prefer to pour in the yeast, and this practise is customary with wheat beers. Typically when serving a hefeweizen 90% of the contents is poured and the remainder swirled to dissolve the sediment before pouring it into the glass.

Beer culture

Gambrinus - king of beerBeer in a social context

See also: Pub games, Pub crawl, Public house, and Category:Drinking culture
Various social traditions and activities are associated with beer drinking, such as playing cards, darts or other games; or visiting a series of different pubs in one evening. Consumption in isolation and excess may be associated with people "drowning their sorrows," while drinking in excess in company may be associated with binge drinking.

Beer around the world

See also: Beer and nationality and Beer consumption by country
Beer is consumed in countries all over the world. There are breweries in Middle Eastern countries such as Iraq and Syria as well as African countries (see African beer) and remote countries such as Mongolia.

Serving

Glassware
Main article: Beer glassware
An appropriate glass is considered desirable by some beer drinkers. Some drinkers of beer may sometimes drink straight from the bottle or can, while others may pour their beer into a vessel before imbibing. Drinking out of a bottle inhibits aromas picked up by the nose, so if a drinker wishes to appreciate a beer's aroma, the beer is first poured into a glass, mug, tankard, or stein. Some breweries produce glassware intended for their own beers. Some aficionados claim that the shape and material of the vessel influences the perception of the aroma and the way in which the beer settles, similar to claims by drinkers of brandy or cognac. Some drinkers in Britain prefer their ale to be served in pewter tankards, while in Europe it is common for glasses to be rinsed just before beer is poured into them. While glass is completely non-porous, its surface can retain oil from the skin, aerosolized oil from nearby cooking, and traces of fat from food. When these oils come in contact with beer there is a significant reduction in the amount of head (foam) that is found on the beer, and the bubbles will tend to stick to the side of the glass rather than rising to the surface as normal.

Temperature
The temperature of a beer has an influence on a drinker's experience. Colder temperatures start to inhibit the chemical senses of the tongue and throat, which narrow down the flavour profile of a beer, allowing fully attenuated beers such as Pilsners and Pale lagers to be enjoyed for their crispness, but preventing the more rounded flavours of an ale or a stout from being perceived. While there are no firmly agreed principles for all cases, a general approach is that lighter coloured beers, such as Pale lagers, are usually enjoyed cold (40-45F/4-7C), while dark, strong beers such as Imperial Stouts are often enjoyed at cellar temperature (54-60F/12-16C) and then allowed to warm up in the room to individual taste. Other beers should be served at temperatures between these extremes.

Pouring
The pouring process has an influence on a beer's presentation.

The rate of flow from the tap or other serving vessel, tilt of the glass, and position of the pour (in the center or down the side) into the glass all influence the end result, such as the size and longevity of the head, lacing (the pattern left by the head as it moves down the glass as the beer is drunk), and turbulence of the beer and its release of carbonation.

Unfiltered bottled beers may be served with the addition of the remaining yeast at the bottom of the bottle to add both flavour and colour.

Rating beer

Main article: Rating beer
Rating beer is a recent craze that combines the enjoyment of beer drinking with the hobby of collecting. People drink beer and then record their scores and comments on various internet websites. This is a worldwide activity and people in the USA will swap bottles of beer with people living in New Zealand and Russia. People's scores may be tallied together to create lists of the most popular beers in each country as well as the most highly rated beers in the world.

Health effects

Main articles: Alcohol consumption and health and Beer belly
Beer contains alcohol which has a number of health risks and benefits. However, beer includes a wide variety of other agents that are currently undergoing scientific evaluation.

Nutritionally, beer can contain significant amounts of magnesium, selenium, potassium, phosphorus, biotin, and B vitamins. Typically, the darker the brew, the more nutrient dense.

A 2005 Japanese study found that non-alcoholic beer may possess strong anti-cancer properties. [1]. Another study found non-alcoholic beer to mirror the cardiovascular benefits associated with moderate consumption of alcoholic beverages. [2]

It is considered that over-eating and lack of muscle tone is the main cause of a beer belly, rather than beer consumption.

The Strongest Beers In The World
Beer strength varies by local custom. British ale tends to average 4.4% abv. Belgian beers tend to average 8% abv. The strength of the typical global pale lager is 5% abv. The yeast used for brewing beer normally cannot get the strength much beyond 12% abv; however, in the 1980s the Swiss brewery Hurlimann developed a yeast strain which could get as high as 14% for their Samichlaus beer. Since then breweries have experimented with using champagne yeasts, continually pushing up the strength. Samuel Adams reached 20% abv with Millennium. The strongest beer sold in Britain was Dogfish Head's World Wide Stout, a 21% abv stout which was available from UK Safeways in 2003. In Japan in 2005, the Hakusekikan Beer Restaurant sold an eisbock, strengthened through freezing, believed to be 28% abv. The beer that is considered to be the strongest yet made is Hair of the Dog's Dave - a 29% abv barley wine made in 1994.

Related beverages
There are a number of related beverages such as kvass, sahti and pulque.

Africa: Hundreds of local drinks made from millet, sorghum, and other available starch crops.
Andes, South America: Chicha, an Andean beverage made from germinated maize.
Bhutan, Nepal, Tibet and Sikkim: Chhaang, a popular semi-fermented rice/millet drink in the eastern Himalaya.
China: Jiu, the word refers to all alcoholic drinks, most of which are cheap distilled liquors (baijiu), but there are traditional grain-based relatives of beer such as sulima, made by the Mosuo people and Lijiang Yinjiu, made by the Nakhi people, both in the Lijiang region of Yunnan.
Finland: Sahti, a traditional Finnish beer.
Japan: Sake, a primarily rice-based fermented drink.
Korea: Soju
Kyrgyzstan: Bozo is a low alcohol, somewhat porridgey drink made from millet. The Kyrgyz are also fans of kumis, (in Kyrgyz called kymyz), the fermented mare's milk drink popular in many parts of Central Asia and Mongolia. This is very easy to obtain as it is sold in any market and at small stands on the side of the highway in rural areas as a source of income for the local nomads.
Mexico: Pulque, an indigenous beer made from the fermented sap of the agave plant.
Russia/Ukraine: Kvass, a fermented non-alcoholic or mildly alcoholic beverage.
Various regions: Rye beer, mead (made from water and honey), cider (made from apple juice)
Some Celtic peoples of the European Iron Age drank, according to some classical sources, a type of beer known as korma.
See also
Wikimedia Commons has media related to:
BeerWikibooks has more about this subject:
BrewingBrewery
Brewing
History of beer
Homebrewing
Category:Beer and breweries by region
Non-alcoholic beer
Reinheitsgebot - regulation concerning standards for the sale and composition of beer
Vores Øl - An Open Source Beer
List of countries ordered by per capita beer consumption
External links
RateBeer
Beer Advocate
Cervisia in the Latin Vicipaedia, for the names of local types of beer in Roman times
Beer Wiki
References
The Complete Guide to World Beer, Roger Protz. ISBN 1844428656.
The Barbarian's Beverage: a history of beer in ancient Europe, Max Nelson. ISBN 0415311217.
The World Guide to Beer, Michael Jackson. ISBN 1850760004
Beer: The Story of the Pint, Martyn Cornell. ISBN 0755311655
Beer and Britannia: An Inebriated History of Britain, Peter Haydon. ISBN 0750927488
The Book of Beer Knowledge: Essential Wisdom for the Discerning Drinker, a Useful Miscellany, Jeff Evans. ISBN 1852491981
Country House Brewing in England, 1500-1900, Pamela Sambrook. ISBN 1852851279
Ale, Beer and Brewsters in England: Women's Work in a Changing World, 1300-1600 , Judith M. Bennett. ISBN 0195126505
A History of Beer and Brewing, I. Hornsey. ISBN 0854046305
Beer: an Illustrated History, Brian Glover. ISBN 1840385979
Beer in America: The Early Years 1587-1840 - Beer's Role in the Settling of America and the Birth of a Nation, Gregg Smith. ISBN 0937381659
Big Book of Beer, Adrian Tierney-Jones. ISBN 1852492120
Gone for a Burton: Memories from a Great British Heritage, Bob Ricketts. ISBN 1905203691
Farmhouse Ales: Culture and Craftsmanship in the Belgian Tradition, Phil Marowski. ISBN 0937381845
The World Encyclopedia of Beer, Brian Glover. ISBN 0754809331
The Complete Joy of Homebrewing, Charlie Papazian ISBN 0380772876 (This is the seminal work on home brewing that is almost universally suggested to new hobbyist)

http://en.wikipedia.org/wiki/Beer

Brewery
From Wikipedia, the free encyclopedia

A brewery can be a building or place that produces beer, or a business involved in the production of beer. Breweries can take up multiple city blocks, or be a collection of equipment in a homebrewer's kitchen. The diversity of size in breweries is matched by the diversity of processes, degrees of automation, and kinds of beer produced in breweries. Typically a brewery is divided into distinct sections, with each section reserved for one part of the brewing process.

History

A 16th century brewerySee also: History of beer
The oldest brewery in the world still in operation is believed to be the Bavarian State-owned brewery Weihenstephan, found in the German city of the same name, which can trace its history back to 1040. Although the Zatec brewery in Czech Republic claims it can prove paying beer tax in 1004.

The industrialization of the brewery
Beer, in some form, can be traced back almost 5000 years to Mesopotamian writings describing daily rations of beer and bread to workers. Before the rise of production breweries the production of beer took place at home and was the domain of women, as baking and brewing were seen as "women's work". Breweries, as production facilities reserved for making beer, did not emerge until monasteries and other Christian institutions started producing beer not only for their own consumption, but also to use as payment. This industrialization of brewing shifted the responsibility of making beer to men.

Early breweries were almost always built on multiple storeys, with equipment on higher floors utilized earlier in the production process, so that gravity could assist with the transfer of product from one stage to the next. This layout is often preserved in breweries today, but mechanical pumps allow more flexibility in brewery design.

Early breweries typically used large copper vats in the brewhouse, and fermentation and packaging took place in lined wooden containers. Such breweries were common until the Industrial Revolution, when better materials became available, and scientific advances led to a better understanding of the brewing process. Today, almost all breweries are made of stainless steel.

[edit]
Major technological advances
A handful of major breakthroughs have led to the modern brewery and its ability to produce the same beer consistently.

The steam engine, vastly improved in 1765 by James Watt, brought automatic stirring mechanisms, and pumps into the brewery. It gave brewers the ability to more reliably mix liquids while heating, particularly the mash, to prevent scorching, and a quick way to transfer liquid from one container to another. Almost all breweries now use electric-powered stirring mechanisms and pumps. The steam engine also allowed the brewer to make greater quantities of beer, as human power was no longer a limiting factor in moving and stirring.

Carl von Linde, along with several other people, is credited with developing the refrigeration machine in 1871. Refrigeration allowed beer to be produced year-round, and always at the same temperature. Yeast is very sensitive to temperature, and if a beer was produced during summer, the yeast would impart unpleasant flavors onto the beer. Most brewers would produce enough beer during winter to last through the summer, and store it in underground cellars, or even caves, to protect it from summer's heat.

Most importantly, the discovery of microbes by Louis Pasteur was instrumental in the control of fermentation. The idea that yeast was a microorganism that worked on wort to produce beer lead to the isolation of a single yeast cell by Emil Christian Hansen. Pure yeast cultures allow brewers to pick out yeasts for their fermentation characteristics, including flavor profiles and fermentation ability. Some breweries in Belgium still rely on "spontaneous" fermentation for their beers (see lambic).

The modern brewery
Breweries today are made predominantly of stainless steel, although vessels often have a decorative copper cladding for a nostalgic look. Stainless steel has many favorable characteristics which make it a well-suited material for brewing equipment. It imparts no flavor in beer, it reacts with very few chemicals, which means almost any cleaning solution can be used on it (concentrated chlorine bleach being a notable exception) and it is very sturdy. Sturdiness is important, as most tanks in the brewery have positive pressure applied to them as a matter of course, and it is not unusual that a vacuum will be formed incidentally during cleaning.

Heating in the brewhouse is usually achieved through pressurized steam, although direct-fire systems are not unusual in small breweries. Similarly, cooling in other areas of the brewery is typically done by cooling jackets on tanks, which allow the brewer to precisely control the temperature on each tank individually, although whole-room cooling is also common.

Today modern brewing plants perform myriad analyses on their beers for quality control purposes. Shipments of ingredients are analyzed in order to correct for variations; Samples are pulled at almost every step and tested for oxygen content, unwanted microbial infections, and other beer-aging compounds; and a representative sample of the finished product is often stored for months for comparison when complaints are filed.

[edit]
The Brewing Process
Main article: Brewing
Work in the brewery is typically divided into 7 steps: Mashing, Lautering, Boiling, Fermenting, Conditioning, Filtering, and Filling.

[edit]
Mashing
Mashing is the process of mixing milled grain (typically malted grain) with water, and heating this mixture up with rests at certain temperatures to allow enzymes in the malt to break down the starch in the grain into sugars, typically maltose.

Lautering
Lautering is the separation of the extracts won during mashing from the spent grain to create wort. It is achieved in either a Lauter tun, a wide vessel with a false bottom, or a mash filter, a plate-and-frame filter designed for this kind of separation. Lautering has two stages: first wort run-off, during which the extract is separated in an undiluted state from the spent grains, and sparging, in which extract which remains with the grains is rinsed off with hot water.

Boiling
Boiling the wort ensures its sterility, and thus prevents a lot of infections. During the boil, hops are added, which contribute their bitter aromas and flavor compounds to the beer, and, along with the heat of the boil, causes proteins in the wort to coagulate and the pH of the wort to fall. Finally, the vapors produced during the boil volatilize off flavors, including dimethyl sulfide precursors.

The boil must be conducted so that is it even and intense. The boil lasts between 60 and 120 minutes, depending on its intensity, the hop addition schedule, and volume of wort the brewer expects to evaporate.

Fermenting
Fermentation, as a step in the brewing process, starts as soon as yeast is added to the cooled wort. This is also the point at which the product is first called beer. It is during this stage that sugars won from the malt are metabolized into alcohol and carbon dioxide. Fermentation tanks come in all sorts of forms, from enormous tanks which can look like storage silos, to five gallon glass carboys in a homebrewer's closet.

Most breweries today use cylindroconical vessels, or CCVs, have a conical bottom and a cylindrical top. The cone's aperture is typically around 60°, an angle that will allow the yeast to flow towards the cones apex, but is not so steep as to take up too much vertical space. CCVs can handle both fermenting and conditioning in the same tank. At the end of fermentation, the yeast and other solids which have fallen to the cones apex can be simply flushed out a port at the apex.

Open fermentation vessels are also used, often for show in brewpubs, and in Europe in wheat beer fermentation. These vessels have no tops, which makes harvesting top fermenting yeasts very easy. The open tops of the vessels make the risk of infection greater, but with proper cleaning procedures and careful protocol about who enters fermentation chambers when, the risk can be well controlled.

Fermentation tanks are typically made of stainless steel. If they are simple cylindrical tanks with beveled ends, they are arranged vertically, as opposed to conditioning tanks which are usually laid out horizontally.

A very few breweries still use wooden vats for fermentation as wood is difficult to keep clean and infection-free and must be repitched more or less yearly.

After high kraeusen, a bung device (German: Spundapparat) is often put on the tanks to allow the CO2 produced by the yeast to naturally carbonate the beer. This bung device can be set to a given pressure to match the type of beer being produced. The more pressure the bung holds back, the more carbonated the beer becomes.

Conditioning
When the sugars in the fermenting beer have been almost completely digested, the fermentation slows down and the yeast starts to settle to the bottom of the tank. At this stage, the beer is cooled to around freezing, which encourages settling of the yeast, and causes proteins to coagulate and settle out with the yeast. Unpleasant flavors such as phenolic compounds become insoluble in the cold beer, and the beer's flavor becomes smoother. During this time pressure is maintained on the tanks to prevent the beer from going flat.

If the fermentation tanks have cooling jackets on them, as opposed to the whole fermentation cellar being cooled, conditioning can take place in the same tank as fermentation. Otherwise separate tanks (in a separate cellar) must be employed.

Filtering
Filtering the beer stabilizes the flavour, and gives beer its polished shine and brilliance. Not all beer is filtered. When tax determination is required by local laws, it is typically done at this stage in a calibrated tank.

Filters come in many types. Many use pre-made filtration media such as sheets or candles, while others use a fine powder made of, for example, diatomaceous earth, also called kieselguhr, which is introduced into the beer and recirculated past screens to form a filtration bed.

Filters range from rough filters that remove much of the yeast and any solids (e.g. hops, grain particles) left in the beer, to filters tight enough to strain color and body from the beer. Normally used filtration ratings are divided into rough, fine and sterile. Rough filtration leaves some cloudiness in the beer, but it is noticeably clearer than unfiltered beer. Fine filtration gives a glass of beer that you could read a newspaper through, with no noticeable cloudiness. Finally, as its name implies, sterile filtration is fine enough that almost all microorganisms in the beer are removed during the filtration process.

Packaging
Packaging is putting the beer into the containers in which it will leave the brewery. Typically this means in labelled bottles, kegs and casks, but it might include bulk tanks for high-volume customers.

Some brewery descriptions

Skol brewery in Uran, New Bombay, India.Breweries range widely in the volume and variety of beer produced, ranging from small breweries that produce a few dozen barrels a year, to massive multinational conglomerates, such as InBev, that produce hundreds of millions of barrels annually. Some commonly used descriptions of breweries are:

Microbrewery – A late 20th century name for a small brewery. The term started to be replaced with craft brewer at the start of the 21st century.
Brewpub – A brewery whose beer is brewed primarily on the same site from which it is sold to the public, such as a pub or restaurant. If the amount of beer that a brewpub distributes off-site beer exceeds 75%, it may also be described as a craft or microbrewery.
Contract brewing company or contract brewery – A business that hires another brewery to produce its beer. The contract brewing company generally handles all of the beers marketing, sales, and distribution, while leaving the brewing and packaging to the producer-brewery (which, confusingly, is also sometimes referred to as a contract brewer).
Regional brewery – An established term for a brewery that supplies beer in a fixed geographical location. With modern distribution methods this term is falling out of use.
Craft brewer – A term that is replacing microbrewery. A craft brewery is a brewery which does not use adjuncts and/or is considered to make craft beer.
Macrobrewery– A negative term for a large brewery.
A brewmaster is a person who is in charge of the production of beer. The major breweries employ engineers with a Chemistry/Biotechnology background. Brewmaster is here given to a person after 2½ years of extra study in the art of brewing thus earning a degree equivalent to a Ph.D.

Craft Brewing
Before Prohibition in the United States, breweries were local institutions, with a few exceptions. The costs involved in moving large quantities of beer while maintaining its quality necessitated that beer be made near where it was to be consumed. Prohibition, as could be expected, closed most of the breweries in the United States, and the few that were able to remain open by producing near beer, malt extract, yeast, and other beer-related products, were in an advantageous position to produce and sell beer after Prohibition was lifted. During Prohibition, the advancements in refrigeration and motorvehicles made large regional and national breweries possible. These remaining breweries quickly became large enough to be household names all over the nation, and concentrated mostly on the style with the broadest appeal: American light lagers. Local breweries, with their niche beers, were lost in America.

In 1978, Jimmy Carter signed into law a bill explicitly allowing people to brew beer for private consumption. As the homebrewing movement grew, homebrewers looked to re-create beers they had enjoyed in places with a more varied beer assortment. The rise of imported beers and homebrewing brought a demand for more beer styles, and locally brewed beer. Answering this need, smaller breweries started popping up across America, and a whole industry grew around the microbrewing industry. Many of these startup microbreweries, such as St. Paul's Summit Brewing Company, have since grown into major regional breweries in their own right.

Portland, Oregon has earned the name "Beervana", with more breweries than any other city in the world. With a mind-numbing 33 breweries just within the city limits. The McMenamin brothers alone have over thirty brewpubs, distilleries and wineries scattered throughout the metropolitan area, many in renovated theaters and other old buildings otherwise destined for demolition. Other notable Portland brewers include Widmer Brothers, Bridgeport Brewing Company and the MacTarnahan's Brewing Company. In 1999, "beerhunter" and author Michael Jackson called Portland a candidate for the beer capital of the world because the city boasted more breweries than Cologne, Germany.

The number of craft brewers in the United States has been slowly declining in the last decade, while craft brewers have made up a larger percentage of beer sales in America, likely reflecting a more discriminating customer, who is less tolerant of off flavors and poorly made beers.

See also
Brewing
Beer
Malt
Hops
Homebrewing

References
ISBN 3921690390: Technology Brewing and Malting, Wolfgang Kunze, 2nd revised edtion, VLB Berlin. Available at their website
http://www.beertown.org/craftbrewing/statistics.html: Craft Brewery definitions at the bottom of the page

Brewing
From Wikipedia, the free encyclopedia

Brewing is the production of alcoholic beverages and alcohol fuel through fermentation. This is the method used in beer production, although the term can be used for other drinks such as sake, mead and wine. The term is also sometimes used to refer to any chemical mixing process.

Brewing has a very long history, and archeological evidence tells us that this technique was used in ancient Egypt. Descriptions of various beer recipes can be found in Sumerian writings, some of the oldest known writing of any sort.

The brewing industry is part of most western economies.

Contents [hide]
1 Brewing beer
1.1 Ale (top fermenting yeasts)
1.2 Lager (bottom fermenting yeasts)
1.3 Beers of Spontaneous Fermentation (wild yeasts)
1.4 Beers of mixed origin
2 The Brewing Process
2.1 Mashing
2.2 Lautering
2.2.1 Lauter tun
2.2.2 Mash Filter
2.3 Boiling
2.3.1 Boiling equipment
2.3.2 Energy recovery
2.3.3 Whirlpool
2.3.4 Wort cooling
2.4 Fermenting
2.5 Conditioning
2.6 Filtering
2.6.1 Sheet (pad) filters
2.6.2 Kieselguhr filters
2.7 Packaging
2.8 Secondary fermentation
3 See also
4 External links

[edit]
Brewing beer
All beers are brewed using a process based on a simple formula. Key to the process is malted grain, depending on the region traditionally barley, wheat or sometimes rye. (When malting rye, due care must be taken to prevent ergot poisoning (ergotism), as rye is particularly prone to developing this toxic fungus during the malting process.)

Malt is made by allowing a grain to germinate, after which it is then dried in a kiln and sometimes roasted. The germination process creates a number of enzymes, notably a-amylase and ß-amylase, which will be used to convert the starch in the grain into sugar. Depending on the amount of roasting, the malt will take on dark colour and strongly influence the colour and flavour of the beer.

The malt is crushed to break apart the grain kernels, increase their surface area, and separate the smaller pieces from the husks. The resulting grist is mixed with heated water in a vat called a "mash tun" for a process known as "mashing". During this process, natural enzymes within the malt break down much of the starch into sugars which play a vital part in the fermentation process. Mashing usually takes 1 to 2 hours, and during this time various temperature rests (waiting periods) activate different enzymes depending upon the type of malt being used, its modification level, and the desires of the brewmaster. The activity of these enzymes convert the starches of the grains to dextrines and then to fermentable sugars such as maltose. The Mash Tun generally contains a slotted "false bottom" or other form of manifold which acts as a strainer allowing for the separation of the liquid from the grain.

A mash rest at 104 °F or 40 °C activates beta-glucanase, which breaks down gummy beta-glucans in the mash, making the sugars flow out more freely later in the process. In the modern mashing process commercial fungal based beta-glucanase may be added as a supplement. A mash rest from 120 °F to 130 °F (49 °C to 55 °C) activates various proteinases, which break down proteins that might otherwise cause the beer to be hazy. But care is of the essence since the head on beer is also composed primarily of proteins, so too aggressive a protein rest can result in a beer that cannot hold a head. This rest is generally used only with undermodified (i.e. undermalted) malts which are decreasingly popular in Germany and the Czech Republic, or non-malted grains such as corn and rice, which are widely used in North American beers. Finally, a mash rest temperature of 149 to 160 °F (65 to 71 °C) is used to convert the starches in the malt to sugar, which is then usable by the yeast later in the brewing process. Doing the latter rest at the lower end of the range produces more low-order sugars which are more fermentable by the yeast. This in turn creates a beer lower in body and higher in alcohol. A rest closer to the higher end of the range creates more higher-order sugars which are less fermentable by the yeast, so a fuller-bodied beer with less alcohol is the result.

After the mashing, the resulting liquid is strained from the grains in a process known as lautering. Prior to lautering, the mash temperature may be raised to 165 °F to 170 °F (about 75 °C) (known as a mashout) to deactivate enzymes. Additional water may be sprinkled on the grains to extract additional sugars (a process known as sparging).

At this point the liquid is known as wort (rhymes with hurt). The wort is moved into a large tank known as a "copper" or kettle where it is boiled with hops and sometimes other ingredients such as herbs or sugars. The boiling process serves to terminate enzymatic processes, precipitate proteins, isomerize hop resins, concentrate and sterilize the wort. Hops add flavour, aroma and bitterness to the beer. At the end of the boil, the hopped wort settles to clarify it in a vessel called a "whirl-pool" and the clarified wort is then cooled.

The wort is then moved into a "fermentation vessel" where yeast is added or "pitched" with it. The yeast converts the sugars from the malt into alcohol, carbon dioxide and other components through a process called Glycolysis. After a week to three weeks, the fresh (or "green") beer is run off into conditioning tanks. After conditioning for a week to several months, the beer is often filtered to remove yeast and particulates. The "bright beer" is then ready for serving or packaging.

There are four main families of beer styles determined by the variety of yeast used in their brewing.

Ale (top fermenting yeasts)
Ale yeasts ferment at warmer temperatures between 15°C and 20°C (60°F to 68°F), and occasionally as high as 24°C (75°F). Pure ale yeasts form a foam on the surface of the fermenting beer, because of this they are often referred to as Top Fermenting yeast - though there are some British ale yeast strains that settle at the bottom. Ales are generally ready to drink within three weeks after the beginning of fermentation, however, some styles benefit from additional aging for several months or years. Ales range in color from very pale to black opaque. England is best known for its variety of Ales.

Lager (bottom fermenting yeasts)
While the nature of yeast was not fully understood until Emil Hansen of the Carlsberg brewery in Denmark isolated a single yeast cell in the 1800s, brewers in Bavaria had for centuries been selecting these cold-fermenting Lager yeasts by storing or "Lagern" their beers in cold alpine caves. The process of natural selection meant that the wild yeasts that were most cold tolerant would be the ones that would remain actively fermenting in the beer that was stored in the caves. Some of these Bavarian yeasts were stolen and brought back to the Carlsberg brewery around the time that Hansen did his famous work.

Lager yeast tends to collect at the bottom of the fermenter and is often referred to as Bottom Fermenting yeast. Lager is fermented at much lower temperatures, around 10°C (50°F), compared to typical ale fermentation temperatures of 18°C (65°F). It is then stored for 30 days or longer close to the freezing point. During the storing or Lagering process, the beer mellows and flavours become smoother. Sulfur components developed during fermentation dissipate. The popularity of lager was a major factor that led to the rapid introduction of refrigeration in the early 1900s.

Today, lagers represent the vast majority of beers produced, the most famous being a light lager called Pilsner which originated in Pilsen, Czech Republic (Plzen in czech language). It is a common misconception that all Lagers are light in color: lagers can range from very light to deep black, just like Ales.

Beers of Spontaneous Fermentation (wild yeasts)
These beers are nowadays primarily only brewed around Brussels, Belgium. They are fermented by means of wild yeast strains that live in a part of the Zenne river which flows through Brussels. These beers are also called Lambic beers. However with the advent of yeast banks and the NCYC, brewing these beers, although not through spontaneous fermentation, is possible anywhere.

Beers of mixed origin
These beers are blends of spontaneous fermentation beers and ales or lagers or they are ales/lagers which are also fermented by wild yeasts.

The Brewing Process
Work in the brewery is typically divided into 7 steps: Mashing, Lautering, Boiling, Fermenting, Conditioning, Filtering, and Filling.

Mashing
Main article: Mashing
Mashing is the process of mixing milled grain (typically malted grain) with water, and heating this mixture up with rests at certain temperatures to allow enzymes in the malt to break down the starch in the grain into sugars, typically maltose.

Boilers at the Samuel Adams brewery[edit]
Lautering
Lautering is the separation of the extracts won during mashing from the spent grain. It is achieved in either a Lauter tun, a wide vessel with a false bottom, or a mash filter, a plate-and-frame filter designed for this kind of separation. Lautering has two stages: first wort run-off, during which the extract is separated in an undiluted state from the spent grains, and sparging, in which extract which remains with the grains is rinsed off with hot water.

Lauter tun
A lauter tun is the traditional vessel used for separation of the extracted wort. While the basic principle of its operation has remained the same since its first use, technological advances have led to better designed lauter tuns capable of quicker and more complete extraction of the sugars from the grain.

The false bottom in a lauter tun has thin (0.7 to 1.1 mm) slits to hold back the solids and allow liquids to pass through. The solids, not the false bottom, form a filtration medium and hold back small solids, allowing the otherwise cloudy mash to run out of the lauter tun as a clear liquid. The false bottom of a lauter tun is today made of wedge wire, which can provide a free-flow surface of up to 12% of the bottom of the tun.

The run off tubes should be evenly distributed across the bottom, with one tube servicing about 1 m² of area. Typically these tubes have a wide, shallow cone around them to prevent drastic forces from compacting the grain directly above the outlet. In the past the run-off tubes flowed through swan-neck valves into a wort collection grant. While visually stunning, this system led to a lot of oxygen uptake. Such a system has mostly been replaced either by a central wort-collection vessel or the arrangement of outlet ports into concentric zones, with each zone having a ring-shaped collection pipe. Brewhouses in plain public view, particularly those in brewpubs, often maintain the swan-neck valves and grant for their visual effect.

A quality lauter tun has rotating rake arms with a central drive unit. Depending on the size of the lauter tun, there can be between two and six rake arms. Cutting blades hang from these arms. The blade is usually wavy and has a plough-like foot. Each blade has its own path around the tun and the whole rake assembly can be raised and lowered. Attached to each of these arms is a flap which can be raised and lowered for pushing the spend grains out of the tun. The brewer, or better yet an automated system, can raise and lower the rake arms depending on the turbidity (cloudiness) of the run-off, and the tightness of the grain bed, as measured by the pressure difference between the top and bottom of the grain bed.

There must be a system for introducing sparge water into the lauter tun. Most systems have a ring of spray heads that insure an even and gentle introduction of the sparge water. The watering system should not beat down on the grain bed and form a channel.

Large breweries have self-closing inlets on the bottom of the tun through which the mash is transferred to the lauter tun, and one outlet, also on the bottom of the tun, into which the spent grains fall after lautering is complete. Craft breweries often have manways on the side of the mash tun for spent grain removal, which then must be helped along to a large extent by the brewer.

Some small breweries use a combination mash/lauter tun, in which the rake system cannot be implemented because the mixing mechanism for mashing is of higher importance. The stirring blades can be used as an ersatz rake, but typically they cannot be moved up and down, and would disturb the bed too much were they used deep in the grain bed.

Mash Filter
A mash filter is a plate-and-frame filter. The empty frames contain the mash, including the spent grains, and have a capacity of around one hectoliter. The plates contain a support structure for the filter cloth The plates, frames, and filter cloths are arranged in a carrier frame like so: frame, cloth, plate, cloth, with plates at each end of the structure. Newer mash filters have bladders that can press the liquid out of the grains between spargings. The grain does not act like a filtration medium in a mash filter.

Boiling
Boiling the won extracts, called wort, ensures its sterility, and thus prevents a lot of infections. During the boil hops are added, which contribute bitterness, flavor, and aroma compounds to the beer, and, along with the heat of the boil, causes proteins in the wort to coagulate and the pH of the wort to fall. Finally, the vapors produced during the boil volatilize off flavors, including dimethyl sulfide precursors.

The boil must be conducted so that is it even and intense. The boil lasts between 50 and 120 minutes, depending on its intensity, the hop addition schedule, and volume of wort the brewer expects to evaporate.

Boiling equipment
The simplest boil kettles are direct-fired, with a burner underneath. These can produce a vigorous and favorable boil, but are also apt to scorch the wort where the flame touches the kettle, causing caramelization and making clean up difficult.

Most breweries use a steam-fired kettle, which uses steam jackets in the kettle to boil the wort. The steam is delivered under pressure by an external boiler.

State-of-the-art breweries today use many interesting boiling methods, all of which achieve a more intense boiling and a more complete realization of the goals of boiling.

Many breweries have a boiling unit outside of the kettle, sometimes called a calandria, through which wort is pumped. The unit is usually a tall, thin cylinder, with many tubes upwards through it. These tubes provide an enormous surface area on which vapor bubbles can nucleate, and thus provides for excellent volitization. The total volume of wort is circulated seven to twelve times an hour through this external boiler, insuring that the wort is evenly boiled by the end of the boil. The wort is then boiled in the kettle at atmospheric pressure, and through careful control the inlets and outlets on the external boiler, an overpressure can be achieve in the external boiler, raising the boiling point a few Celsius degrees. Upon return to the boil kettle, a vigorous vaporization occurs. The higher temperature due to increased vaporization can reduce boil times up to 30%. External boilers were originally designed to improve performance of kettles which did not provide adequate boiling effect, but have since been adopted by the industry as a sole means of boiling wort.

Modern brewhouses can also be equipped with internal calandria, which requires no pump. It works on basically the same principle as external units, but relies on convection to move wort through the boiler. This can prevent overboiling, as a deflector above the boiler reduces foaming, and also reduces evaporation. Internal calandria are generally difficult to clean.

Energy recovery
Boiling wort takes a lot of energy, and it is wasteful to let this energy escape into the atmosphere. The simplest was to recover this energy is with a kettle vapor condenser (German: Pfaduko, from the much longer Pfannendunstkondensator). A kettle vapor condenser is often nothing more than a plate heat exchanger.

Whirlpool
At the end of the boil, the wort is set into a whirlpool. The so-called teacup effect forces the more dense solids (coagulated proteins, vegetable matter from hops) into a cone in the center of the whirlpool tank.

In most large breweries, there is a separate tank for whirlpooling. These tanks have a large diameter to encourage settling, a flat bottom, a tangential inlet near the bottom of the whirlpool, and an outlet on the bottom near the outer edge of the whirlpool. A whirlpool should have no internal protrusions that might slow down the rotation of the liquid. The bottom of the whirlpool is often slightly sloped towards the outlet. Newer whirlpools often have "Denk rings" suspended in the middle of the whirlpool. These rings are aligned horizontally and have about 75% of the diameter of the whirlpool. The Denk rings prevent the formation of secondary eddies in the whirlpool, encouraging the formation of a cohesive trub cone in the middle of the whirlpool.

Smaller breweries often use the brewkettle as a whirlpool.

Wort cooling
After the whirlpool, the wort must be brought down to fermentation temperatures before yeast is added. In modern breweries this is achieved through a plate heat exchanger. A plate heat exchanger has many ridged plates, which form two separate paths. The wort is pumped into the heat exchanger, and goes through every other gap between the plates. The cooling medium, usually water, goes through the other gaps. The ridges in the plates ensure turbulent flow. A good heat exchanger can drop 95 °C wort to 20 °C while warming the cooling medium from about 10 °C to 80 °C. The last few plates often use a cooling medium which can be cooled to below the freezing point, which allows a finer control over the wort-out temperature, and also enables cooling to around 10 °C. After cooling, oxygen is often dissolved into the wort to revitalize the yeast and aid its reproduction.

Fermenting

Modern fermenting tanksFermentation, as a step in the brewing process, starts as soon as yeast is added to the cooled wort. This is also the point at which the product is first called beer. It is during this stage that sugars won from the malt are metabolized into alcohol and carbon dioxide. Fermentation tanks come in all sorts of forms, from enormous tanks which can look like storage silos, to five gallon glass carboys in a homebrewer's closet.

A very few breweries still use wooden vats for fermentation as wood is difficult to keep clean and infection-free and must be repitched more or less yearly.

After high kraeusen a bung device (German: Spundapparat) is often put on the tanks to allow the CO2 produced by the yeast to naturally carbonate the beer. This bung device can be set to a given pressure to match the type of beer being produced. The more pressure the bung holds back, the more carbonated the beer becomes.

Filtering

A mixture of diatomaceous earth and yeast after filtering.Main article: Filtered beer
Filtering the beer stabilizes the flavor, and gives beer its polished shine and brilliance. Not all beer is filtered. When tax determination is required by local laws, it is typically done at this stage in a calibrated tank.

Sheet (pad) filters
These filters use pre-made media and are relatively straightforward. The sheets are manufactured to allow only particles smaller than a given size through, and the brewer is free to choose how finely to filter the beer. The sheets are placed into the filtering frame, sterilized (with hot water, for example) and then used to filter the beer. The sheets can be flushed if the filter becomes blocked, and usually the sheets are disposable and are replaced between filtration sessions. Often the sheets contain powdered filtration media to aid in filtration.

It should be kept in mind that pre-made filters have two sides. One with loose holes, and the other with tight holes. Flow goes from the side with loose holes to the side with the tight holes, with the intent that large particles get stuck in the large holes while leaving enough room around the particles and filter medium for smaller particles to go through and get stuck in tighter holes.

Sheets are sold in nominal ratings, and typically 90% of particles larger than the nominal rating are caught by the sheet.

Kieselguhr filters
Filters that use a powder medium are considerably more complicated to operate, but can filter much more beer before needing to be regenerated. Common media include diatomaceous earth, or kieselguhr, and perlite.

Packaging
Packaging is putting the beer into the containers in which it will leave the brewery. Typically this means in bottles and kegs, but it might include bulk tanks for high-volume customers.

Secondary fermentation
Secondary fermentation is an additional fermentation after the first or primary fermentation. Some beers may have three fermentations.

Bottle fermentation

See Bottle conditioning.
Some beers undergo a fermentation in the bottle, giving natural carbonation. This may be a second or third fermentation. They are bottled with a viable yeast population in suspension. If there is no residual fermentable sugar left, sugar may be added. The resulting fermentation generates CO2 which is trapped in the bottle, remaining in solution and providing natural carbonation.

Cask conditioning

See Cask ale.
Beer in casks are managed carefully to allow some of the carbonation to escape.

Beer and nationality
From Wikipedia, the free encyclopedia

What follows is a list of beers by the country within which they originate, and the beer drinking and brewing practices within those countries:

African
See also African beer.

Egypt
See also Egyptian beer.

The leading local brand is called Stella (not to be confused with the Belgian Stella Artois). Available in original, export, and premium varieties, it is primarily sold to non-Muslim overseas visitors. Other brands on the market include Meister and Saqqara, and the non-alcoholic "Birell" and "Kaliber".

Morocco
See also Moroccan beer.

Beer production in Morocco was introduced by the French in the XXth century. Currently, Societe des Brasseries du Maroc oversees the production and distribution. Popular beers include Speciale Flag (pilsner) and Stork (lager). The premium beer is Casablanca (lager) which costs more than the other two. The breweries are located in Fes, Meknes and Casablanca.

Namibia
See Namibian beer.

Nigeria
See also Nigerian beer.

South Africa
See South African beer.

Albania
See also Albanian beer.

Albania's most famous beer is Birra Tirana, which accounts for