Alcohol content
The alcohol content of beer is directly related to the original extract content (US English) or original gravity (UK English). 25 to 34% of the original extract is converted to alcohol. This means that the extract content is approximately 3 times as high as the resulting alcohol content. An entire beer with 11 to 14% original extract has an alcohol content of 4.5 to 5.5 percent. Pils normally has 4.5 to 4.9% and Export from 5.0 to 5.5%. There are, however, Export beers with only 4.5% and Pils with 4.2% or even 5.3%.

Alpha acid
The most important compound in hops due to its high bittering value.

Alt
Originally, almost all beer was top-fermented. Bottom-fermenting yeast could first be used year-round after the invention of refrigeration equipment. Thereafter, the older type, top-fermented, was called "Alt" because it was brewed according to the "old" method. The problem with this name is that there are other top-fermented beers which are not called "Alt". See Top-fermenting or Bottom-fermenting. The Alt beer we know today gets its extraordinary taste and dark color from the use of dark-colored, caramelized malt.

Amylase
Enzymes which can convert starch to malt sugar. They are formed during the germination of the barley and contribute to the wort brewing in the brewhouse.

Annual consumption
The Germans are the world champion beer drinkers with an annual consumption of 138 liters per capita.

Barley
According to the German Beer Purity Law, barley is one of the three ingredients of beer. Two-rowed summer barley is best suited for brewing because of its low protein content. It is converted into malt by germination and kilning before it is used for brewing.

Barrel/keg beer
Approximately 25% of German beer is sold in barrels or kegs.

Beer (Bier)
Beer is a beverage created by the alcoholic fermentation of hops, yeast, malt and water. Only barley malt be used for bottom-fermented beer, while wheat, rye or spelt can be used for top-fermented beer. Beer was man's first alcoholic drink. The brewing of barley malt beer can be traced back to the 4th century BC. See also: The origin and history of beer.

Beer classifications
Beer can be classified into types, kinds, sorts, families, classes, varieties or species using dozens of criteria. The four most common are:
1. Brewing recipe and/or method; These brewing recipes and/or methods have acquired names over the years, by which beer can be ordered irrespective of brand. These names vary from culture to culture around the world, but German names dominate. The most widely consumed German beer is Pils. Alt, Export, Weizen and Koelsch account for most of the rest of German consumption.
2. Color; pale or dark. Dark beers are brewed using roasted (kilned at higher temperatures) malt or dark malt produced by a special malting process.
3. Original extract/gravity content; very low extract/gravity (under 7% by weight), low gravity/extract (7-11%), entire beer or medium extract/gravity (11-14%) and strong ales, malt liquors, barley wines or high extract/gravity (over 16%).
4. Yeast variety; top or bottom-fermenting

Berliner Weisse
Top-fermented beer with 7-8% original extract which is fermented with a mixture of yeast and lactic acid bacteria. As the taste is somewhat sour, Berliner Weisse is normally drunk with a "Schuss" (shot) of raspberry or woodruff syrup.

Bock
Bock is a top or bottom-fermented, high extract/gravity (over 16%) beer, available as pale or dark. The name is a corruption of the town name Einbeck where bock beer was first brewed.

Bottle fermentation
The last stage of fermentation takes place in the bottle. This is induced by adding yeast to the beer in the bottle. The best known example of this method is Hefeweissbier (literally: yeast white beer).

Bottled beer
About 73% of the annual German beer output is bottled, the rest goes into cans or barrels.

Bottom-fermenting
Actually the beer is not bottom-fermenting, the yeast is. Pils, Export, Bock, Doppelbock, Hell, Maerzen and Lager, for example, are bottom-fermented beers. As fermentation takes place at temperatures from 4-10 degrees C, beers of this type could not be brewed the year round until after refrigeration equipment became available in 1876.

Braun beer
Braun (brown) beer is a very low extract/gravity (under 7%) top-fermented beer which gets its name from its color. It is still brewed today in only a very few breweries.

Brewery output
The volume of beer brewed or sold in a given time period. Normally expressed in hectoliter (hl) = 100 liter. The annual German beer output is roughly 100 million hectoliter.

Brewery
In Germany there are almost 1300 brewing locations, in which approximately 6000 brands are brewed. Many of these have traditions dating back several centuries.

Brewhouse
Brewhouses are full of mash tuns, lauter tuns and wort coppers. Crushed malt is mixed with water and saccharified. The liquid, called wort, is separated form the spent grain and subsequently simmered together with hops.

Bulk heading or bunging
The precisely controlled pressurizing of beer storage during the secondary fermentation in order to achieve the desired level of dissolved carbon dioxide.

Calories
That beer has many calories is wrong. Beer, depending on the type, has around 450 kcal (=1870 kJ) per liter. Only water and black coffee or tea have less. Whole milk has over 600, wine, champagne or grape juice 700-800, and spirits 3000 kcal per liter. Beer is a healthy drink. See also Beer and Health.

Canned beer
Beer in cans (in the UK: "tins") was first produced in the USA (where else!) in 1935. Today, beer in cans accounts for only about 2% of the total German output, but cans are much more popular in other countries, notably the USA. Beer in cans is stabilized and/or pasteurized to increase shelf life.

Carbohydrates
When brewers speak of carbohydrates, they are normally referring to grain sugars which are converted to alcohol and carbon dioxide during fermentation.

Carbon dioxide
A gas which is produced during fermentation, under pressure it combines with water to form carbonic acid. This pressure is always existent in closed beer containers as the carbon dioxide tries to escape from the liquid. The pressure is important for beer freshness and keeping quality.

Cellar beer
Normally a dark, cloudy unfiltered beer.

Clarification equipment
During secondary fermentation, the yeast cells sink to the bottom, taking with them much of the haze producing components such as proteins or hop resins. This is the natural beer clarification. This can be accelerated through the use of clarification equipment such as centrifuges.

Clip-lock bottles
Also known as "swing stopper" or "lever closure" bottles. This traditional German closure method has been re-introduced by many breweries for marketing reasons. At first glance these bottles also appear more environmentally friendly.

Coarse-grinding
Before malt can be mixed with water into mash it must be coarsely ground (also referred to as "crushing" or "bruising") in grist mills.

Colloidal stability
Haze causing colloids such as proteins and tannin must be removed from beer. Adsorption stabilization agents which are insoluble in beer are used to collect these colloids and then both are removed.

Components of beer
Carbohydrates, protein, carbon dioxide, alcohol, various minerals and water are the components of beer. For more information see the file on Components of beer.

Diacetyl
Diacetyl is a by-product of the metabolism of yeast during the fermentation process, the majority of which is normally removed by well controlled secondary fermentation. Even slight amounts of diacetyl in beer cause an unpleasant odor and taste.

Diet (low calorie) beer
Reduced carbohydrate beer intended for diabetics. The excess alcohol generated by the carbohydrate reduction is then removed to return the alcohol content to a normal level.

Difference test
Statistical method for determining certifiable differences during sensor evaluation of multiple samples.

Doemens Technical Institute
This institute in Graefelfing trains specialists in brewing and beverage production technology.

Doppelbock
Doppelbock (double bock) is an extra strong bock beer (strong ale or malt liquor) with a minimum of 18% original extract.

Dortmunder
Dortmunder (Dortmund style beer) is a pale, bottom-fermented, entire beer with less hops than Pils (and therefore not so dry). Dortmunder is, however, drier than Munich beer.

Einbeck
The town of Einbeck is the birthplace of bock beer. In the Middle Ages, The dukes of Bavaria enjoyed Einbeck beer so much they hired away the best Einbeck brewmaster.

Entire beer
An old-fashioned but still used expression for "normal strength beer", called "Vollbier" (full beer) in German. According to German law this beer must have 11-14% original extract content. About 96% of German beer is entire beer.

Experimentation and Training Institute Berlin
Together with the School of Agriculture and Brewing Science of the Munich Technical University in Weihenstephan, the two most important research and educational facilities for brewing science.

Export
A pale, bottom-fermented, entire beer, less dry than Pils but usually a bit stronger (minimum 12% original extract). Export was first brewed in the Dortmund area around 1700. Export contains less hops than Pils.

Extract
A valuable component or compound which can withdrawn form a body or liquid. Malt extract is extracted from malt during the mash process. This malt extract dissolved in water is wort.

Fasting beer
An invention of clever monks during the Middle Ages. According to the definition of that time: Liquids do not break the fast.

Fermentation heads (Kraeusen)
A foam layer which accumulates on the surface of beer during fermentation. It consists of bitter substances and protein.

Fermentation
The conversion of malt sugar into alcohol and carbon dioxide through interaction with yeast.

Filling (or bottling)
After the optimum maturation (aging) and filtering procedure for the type of beer involved, the beer is filled into barrels, kegs, bottles or cans. Sterile processing conditions are of maximum importance. Modern bottling plants can fill over 100,000 bottles per hour.

Flavor stability
The ability of a beer to retain the quality it had when it was bottled until it is consumed. The main taste changes are the deterioration of the original harmony and a stale taste. German Agricultural Association quality tests for beer flavor stability consist of the taste- testing of two samples, one "just-bottled" and one older.

Flavor
The flavor of beer depends on many different factors. The choice of various types of grain, water, hops and yeast as well as fermentation and maturation (aging) control are all very important.

Foam
Beer foams (or forms a "head") when poured because carbon dioxide is released. How much foam or how long the head lasts, depends primarily on the amount and type of hops and proteins in the beer.

Forcing test
With this method, the probable non-biological shelf life of beer can be determined through artificial aging. During this test beer is subjected alternating temperatures of 40 or 60 and 0 degrees Celsius.

Foreign organisms
Beer is a natural product. Especially during the initial phase of fermentation, the wort is susceptible to wild yeast and various other fungi as well as bacteria because these organisms thrive under the same conditions as beer yeast. Such foreign organisms can seriously impair or even ruin the taste or keeping qualities of beer. Great care, hygiene and modern brewing technology can prevent such disasters.

Full-bodied taste
The rich, harmonious taste impression of a beer. Of course, this taste impression is primarily dependent on the type and brand of beer.

Fusel oil
An acrid oily liquid created during fermentation, consisting chiefly of amyl alcohol. Higher concentrations can negatively affect quality and digestibility.

Gambrinus
Gambrinus has been regarded the patron saint of brewers for hundreds of years. His exact origin is not clear, some authors claim he was a Burgundian duke of the 13th century, by the name of Jan Primus (John I), others say he was the King of Flanders and Brabant during the 16th century. There is a painting to support the latter theory, which also correlates well with the first use of hops by Brabant monks of that time.

German Beer Purity Law
The German Beer Purity Law is the world's oldest still-valid pure food law. It was decreed by Duke Wilhelm IV of Bavaria in 1516. The decree states that only barley, hops and water may be used in the brewing of beer. Of course, today yeast is also added. In 1516 nobody knew that yeast was also necessary, natural "wild" yeast from the air induced fermentation. Skeptics maintain that the duke was more worried about brewers using scarce wheat or rye for beer. These grains were in short supply and were desperately needed for baking bread.

Germination
Barley (or other brewing grains) must first germinate and subsequently be kilned before they can be used for brewing.

Green beer
After primary fermentation, beer is called green beer. It is then matured (aged) for 4-6 weeks.

Green malt
After being soaked in water, swelling and germinating, barley becomes green malt. It is then dried in kilns.

Grist charge
The amount of malt required for one brew.

Hansen
Emil Christian Hansen scientifically proved the existence of various varieties of yeast. He was the first to successfully propagate yeast in a pure culture.

Haziness (or cloudiness)
Haziness or cloudiness in beer that should be crystal clear can be caused by brewing mistakes, contamination or improper handling. Wild yeast, bacteria, wort residue and proteins can be problematic. Storage temperatures that are too low, such as in the freezer, also cause haze.

Hops
Hops grow on 3-8 meter high shrubs, primarily in southern Germany. The unfertilized female blossoms, referred to as cones or catkins, of cultivated hop plants are used for brewing. Primarily important are the bitter essences and flavor. Hops are one of the 3 ingredients of beer mentioned in the German Beer Purity Law. Hops give beer its characteristic bitter taste, improve its keeping qualities and help make the head last longer. The most prized hops are the flavor hops ("Aromahopfen") from Hallertau in Bavaria.

Keg
In Germany, "keg" means a relatively small cylindrical metal beer barrel equipped with a built-in fitting for easy tapping and subsequent closure and an extractor tube (spear) through which the beer flows. After closure, some carbon dioxide remains in the keg to prevent the beer residue from drying out and prevent the growth of bacteria. In English, of course, any small barrel is a keg.

Kieselguhr
A very fine powder, produced from the remains of prehistoric freshwater or saltwater algae, rich in silicic acid. Kieselguhr (or unconsolidated diatomite) has the ability to bind the sludge particles which produce turbidity. Kieselguhr is used to clarify beer primarily because Kieselguhr itself is not soluble in beer, it forms a filtering layer which only the perfectly clear beer can flow through.

Kilning
Kiln drying of germinated grain.

Koelsch Convention
A voluntary agreement among the Koelsch brewers of the Cologne Brewery Association dated March 1986, which limits the geographical are in which Koelsch may be brewed.

Koelsch
A specialty of the Cologne area. Koelsch is a pale, clear, highly attenuated (fermented), top-fermented beer, brewed according to the German Beer Purity law, with a hops accent and an original extract of a little over 11%. Koelsch may only be brewed in and around Cologne.

Lactic acid
Contamination by lactic acid bacteria can occur at various points in the brewing of beer. The only effective weapons against this contamination are absolute cleanliness and low temperatures. In Berliner Weissen lactic acid bacteria are used on purpose to give the beer its refreshing slightly sour flavor.

Lautering
Upon completion of the mashing process, the "wort" (water with its dissolved extract) is separated from the "spent grain" (residue) in the "lauter tun" (lautering tank).

Lees (Sediment)
Cloudy yeast beers always have yeast lees which can be poured with the beer into the glass or the clear beer above the lees can be carefully poured off. Filtered, clear beer should never leave sediment in the glass.

Light beer
This is a beer with reduced calories and reduced alcohol. Light beer can be produced by removing alcohol from low calorie beer by artificial means or by reducing the original extract content before fermentation. The latter is a more natural method to reduce both the alcohol and calorie content.

Light, influence of
Prolonged exposure of beer to strong natural or artificial light produces an unpleasant taste. Brown bottles provide good protection against light. Green or clear glass bottles should be kept in cartons.

Linde, Carl von
Carl von Linde was the inventor of mechanical refrigeration. Refrigeration equipment first made year round beer brewing possible.

Low alcohol
Low alcohol German beer has a maximum of 1.5% alcohol by weight.

Low gravity beer
Beer with an original extract content (gravity) of 7-11% which is becoming more and more popular in Germany. American "3.2 Beer" is a low gravity beer.

Lupulin
The most valuable component of hop catkins (cones), lupulin is a resin containing the flavoring and bittering essences.

Maerzen
March beer (Maerzen) is a bottom-fermented entire beer, which before von Linde's time, could only be brewed in winter. The last brewing batches (in March) were more strongly fermented so that the higher alcohol content would extend the shelf life over the summer. After the warm summer months, March beer was, and still is today, served at beer festivals (e.g. Octoberfest). Maerzen is also referred to in the German Beer Purity Law.

Maibock
A strong ale (or malt liquor) served in late spring. Its original extract content (original gravity) is at least 16%.

Malt beer
A top-fermented, brown-black beer, in which the 7% original extract content is increased to 12-13% by the addition of sugar (possibly caramelized). Malt beer is an extremely high calorie product with about 1% alcohol or less.

Malt grist (crushed malt)
Malt is crushed (coarsely ground or "bruised") in a grist mill before it mixed with water in the mashing process.

Malting barley
The best barley for brewery use is the two-rowed nodding summer barley. Brewers evaluations of barley are based on aroma, size and form of the grains, glume and endosperm properties as well as the germinability.

Mash
A mixture of coarsely ground malt (grist) and water. Boiling dissolves the almost insoluble starches in the malt grist.

Maturing (aging, storing)
The German verb "lagern" means "to store". After primary fermentation, beer is stored for several weeks in order to mature or age. During this period the secondary fermentation takes place.

Microorganism
Tiny living creatures such as bacteria, yeasts or molds. Undesirable microorganisms are killed by heating.

Monastery breweries
We beer drinkers owe much of our knowledge about the art of brewing to the monasteries. In the Middle Ages, almost every monastery had its own brewery.

Munich beer
A dark, mild entire beer, well-suited to the hard water (high carbonate content) used in early times in Munich.

Non-alcoholic
In Germany, only beer with less than 0.5% alcohol by weight may be called non- alcoholic. In some parts of the world, the name "non-alcoholic brew" is used to avoid confusion, elsewhere the term "low-alcohol" is used to make it clear (for example, to alcoholics) that there is a little alcohol in the beverage.

Non-biological shelf life
The shelf life of a beer from filling until the first visible changes occur.

Original extract content (US English) or original gravity (UK English)
This extract, the nitty-gritty of the wort, the dissolved sugar, protein and bitter essences is called the original extract. The Germans have laws for everything, so of course there is a federal law stating how much original extract a beer must have to bear a specific name. "Starkbier" (similar to malt liquor, strong ale or barley wine) must have at least 16% by weight, "Vollbier" (entire beer or medium extract/gravity), 11-14%, "Schankbier" (low gravity/extract), 7-11%, "Einfachbier" (simple or very low extract/gravity, under 7%). During fermentation, about 1/3 of this extract content becomes alcohol, 1/3 becomes carbon dioxide, and 1/3 is remains as extract.

Oxygen
The intake of oxygen by beer during fermentation should be kept to a minimum because the reaction of oxygen with other beer components reduces shelf life.

Party keg
Most party kegs contain 5 liters. They resemble large cans of beer more than a kegs, but can be tapped with easy to use, specially designed taps. Pouring one's own beer at a party adds to the fun.

Pasteurization
The shelf life of beer can be increased considerably by heating the filled container. This may be necessary if beer is to be exported.

pH value
A scale describing the acidity or alkalinity of a solution. A pH value under 7 indicates acidity, if the value is over 7, the solution is alkaline.

Pils/Pilsener
The name of a type of pale entire beer with a strong hops flavor. Pils is a bottom- fermented beer which was originally brewed only around the town of Pilsen in what is now the Czech Republic. Pils has an original extract content of 12%.

Pilsen
A town in the Czech Republic where the most famous beer type in the world originated.

Pitching, wooden barrels
The coating of wooden barrels with pitch to close holes and joints in order to prevent the escape of carbon dioxide and to provide a smooth inner surface to facilitate cleaning.

Pitching, yeast
The induction of the fermentation process by the addition of yeast to the wort.

Premium beers
Well-advertised and therefore well-known national beer brands.

Pure culture yeast
A selected yeast strain which is ideal for the beer involved and absolutely free from accompanying organisms.

Purity (Aroma or Flavor)
The purity of aroma or flavor can only be determined with a sensory test. This purity must be faultless and typical for the beer type being tested.

Rauchbier
Rauchbier ("smoky beer") owes its name to the fact that the malt used is dried over a wood fire giving the beer a distinct smoky flavor. A specialty of Bamberg.

Saccharification
The conversion of malt starches into sugar by enzymes formed or activated during germination. It takes place mainly during the mash phase at about 63-80 degrees C.

Saccharometer
A special type of hydrometer (or Oechsle meter) for measuring the density of a liquid. In our area of interest, the original extract/gravity (and thereby the roughly proportional sugar concentration) of wort.

Secondary fermentation
Green beer stored in pressurized tanks continues to ferment, matures and increases in carbon dioxide content.

Serving draught beer
Serving draught (US: "draft" or "tap") beer properly is an art in Germany. Beer in kegs or barrels requires careful handling. After being transported, kegs or barrels should be allowed to stand quietly for some time before tapping, otherwise too much foam will be produced. Temperature and the correct glass filling technique are extremely important.

Shelf life
Beer will keep for several months with proper storage, assuming it was brewed according to the German Beer Purity Law without preservatives.

Sludge (or trub)
Protein particles simmered out of the malt during mashing which are removed before fermentation.

Sparkle
An expression for the fresh, lively taste of beer. The carbon dioxide content and pH value play an important role in sparkle.

Spent grain
The insoluble parts of the malt grains, mainly the husks, remain in the lauter tun after the wort has been removed. These parts are referred to as "spent grain" and used as nutritious animal feed.

Spiking
Not putting a shot of whisky in someone's beer, as you might first think, but heating a large spike red-hot and quenching it in your beer glass. First of all this warms the beer because, as any good German will tell you, "Cold drinks are not good for the stomach". Secondly and somewhat more important, some of the sugar caramelizes giving the beer an extra special taste.

Starch
All cereal grains contain starch. Under the proper conditions these starches can be converted to fermentable sugar with the help of the appropriate enzymes.

Steeping
Grain must first be steeped (soaked) in water to induce germination.

Storage requirements
Bottled beer should be stored standing, in a cool, dark place. Although it can be stored for long periods, beer tastes best when consumed within six weeks of purchase.

Top-fermenting
Beers such as Alt, Koelsch, Weissbier, Weizenbier and Berliner Weisse are called top- fermented beers because the yeast cells migrate to the surface of the beer during fermentation. Top-fermentation takes place at about 15-20 degrees Celsius.

Tunnage
The transfer of green beer from the fermentation tanks to the storage (maturing/aging) tanks by pumping through hoses or piping systems.

Water - brewing
According to the German Beer Purity Law, water is one of the three original components of beer: The quality of brewing water is of extreme importance to the quality of the beer made from it and the requirements are very strict. It must at least meet the legal specifications for potable water. Water used by brewers though is often better than the potable water in the surrounding geographical areas. Its taste must be constant and faultless. Water used for brewing must be odorless, clear and free of organisms which could harm the beer or the beer drinker. Mineral salts may be present, but only in certain amounts and of certain types. Brewing water should be soft, that is, have a low carbonate level because hardness has a negative influence on taste and makes it difficult to brew pale beer. Today, about 4.5 liters of water are necessary to brew one liter of beer, a few decades ago, it was 25 liters.

Water - calcium
The hardness of water is expressed in a scale of numbers, the German hardness scale (dH) which reflects the total calcium and magnesium salt content.

Water - carbonates
Calcium, sodium and magnesium salts compounded with carbonic acid. So-called "hard water" is rich in these compounds which negatively influence the brewing of pale beers.

Water - nitrates
Potable water normally contains some nitrates. If the concentration is too high, nitrates can poison yeast and must therefore be removed.

Water - softening
Carbonates are not desirable in brewing water. Water with a high carbonate content is therefore softened using various methods and treatment plants.

Weihenstephan
Site of the oldest still operational brewery in the world. In addition, it is the location of the School of Agriculture and Brewing Science of the Munich Technical University in Weihenstephan (Freising), also known as the Brewing Technology Research and Experimental Facility (Brautechnische Forschungs- und Versuchsanstalt). Together with the Experimentation and Training Institute for Brewing, Berlin, these centers are the two most important research and educational facilities for brewing science in Germany.

Weizenbier
"Weizen" is the German word for wheat, but please don't try to order a "wheat beer" anywhere. The bartender will probably tell you all his beer is weak! Weizenbier is a top- fermented beer brewed with a mixture of barley and wheat malt.

Winter barley
Brewers don't use winter barley unless they have to. Winter barley has too much protein and the husk is too thick.

Wort cooling
After it has been boiled and simmered, wort must be cooled to the right temperature for fermentation. Suspended sludge particles are removed at the same time.

Wort
The "first wort", (soluble malt components dissolved in water) produced during the mashing phase is boiled and then simmered together with hops in the wort coppers until the desired original extract content is achieved. At this point, it is known as "original wort".

Yeast
Yeast is a budding fungus which induces fermentation in the wort. Brewers differentiate between top-fermenting and bottom-fermenting yeasts. As top-fermenting yeast carries out its function in this process, it rises to the surface of the wort, where it stays till fermentation is completed. In contrast, bottom-fermenting yeast sinks to the bottom of the copper during the process and remains there. When top-fermenting yeast has finished its work, it also then sinks to the bottom.

Zymase
An yeast enzyme or enzyme complex that promotes fermentation in monosaccharides.