Beer and brewing terms

Reinheitsgebot

"Purity Law" originating in Bavaria in 1516 and now applied to all German brewers making beer for consumption in their own country. It requires that only malted grains, hops, yeast and water may be used in brewing.

Bomber

A 22 oz bottle of beer

Cask

A barrel shaped container for holding beer.

Gueuze

A beer made with blends of different vintages of lambic

Astringency

A characteristic of beer taste mostly caused by tannins, oxidized (phenols), and various aldehydes (in state beer). This can cause the mouth to pucker and its often perceived dryness.

Acetaldehyde

A chemical and bi product of fermentation that is perceived as green apples in both aromas and flavor.

Boiling

A critical step during the brewing process during which wort (unfermented beer) is boiled inside the brew kettle. During the boiling, one or more hop additions can occur to achieve bittering, hop flavor and hop aroma in the finished beer. Boiling also results in the removal of several volatile compounds from wort, especially dimethyl sulfide (see below) and the coagulation of excess or unwanted proteins in the wort (see "hot break"). Boiling also sterilizes a beer as well as ends enzymatic conversion of proteins to sugars.

Cool Ship

A flat vessel used for cooling wort during the brewing process.

Hydrometer

A glass instrument used to measure the specific gravity of liquids as compared to water consisting of a graduated stem resting on a weighted float.

Dextrin

A group of complex, unfermentable and tasteless carbohydrates produced by the partial hydrolysis of starch, that contributes to the gravity and body of the beer. Some dextrins remain undissolved in the finished beer, giving it a malty sweetness.

Malt Liquor

A legal term used in the US to designate a fermented beverage of relatively high alcohol content (7 to 8% by volume)

Alcohol by Volume (ABV)

A measurement of the alcohol content of a solution in terms of the percentage volume of alcohol per volume of beer. The measurement is always higher than Alcohol by Weight. To calculate the approximate volumetric alcohol content, subtract the final gravity from the original gravity and divide by 0.0075.

Alcohol by Weight (ABW)

A measurement of the alcohol content of a solution in terms of the percentage weight of alcohol per volume of beer. To calculate the alcohol content by weight subtract the final gravity from the original gravity and divide by 0.0095.

Original gravity

A measurement of the density of fermentable sugars in a mixture of malt and water which a brewer begins a given batch

Burton Union

A method of fermentation in which a number of casks are linked together, allowing excess yeast to be removed from the beer. This method also allows the development of a stable strain of yeast over time.

Decoction Mash

A method of mashing that raises the temperature of the mash by removing a portion, boiling it, and returning it to the mash turn. Often uses multiple times in certain mash programs.

Infusion Mash

A method of mashing which achieves target mashing temperatures by the addition of heated water at specific temperatures.

Calcium Carbonate

A mineral common in water. Also known as chalk, sometimes added in the brewing process to increase calcium and carbonate.

Calcium Sulfate

A mineral common in water. Also known as gypsum, sometimes added during brewing to increase calcium and sulfate content.

Freeze Distillation

A process in which beer is lowered to a temperature at which water freezes but alcohol will not. The frozen material is then removed, leaving the beer with a higher alcohol content

Autolysis

A process in which excess yeast cells feed on each other producing a rubbery or vegetable aroma.

Acid Rest

A step done early in the mash around 95F by traditional brewers to lower the ph of the mash.

Conditioning

A step in the brewing process in which beer is matured or aged after initial fermentation to prevent the formation of unwanted flavors and compounds

Alcohol

A synonym for ethyl alcohol or ethanol, the colorless primary alcohol constituent of beer. Alcohol ranges for beer vary from less than 3.2% to greater than 14% ABV. However, the majority of craft beer styles average around 5.9% ABV.

Mash Tun

A tank where grist is soaked in water and heated in order to convert the starch to sugar and extract the sugars and other solubles from the grist.

Brettanomyces

A type of yeast and more specifically a genus of single-celled yeasts that ferment sugar and are important to the beer and wine industries due to the sensory flavors they produce. This yeast can cause acidity and other sensory notes often perceived as leather, barnyard, horse blanket and just plain funk. These characteristics can be desirable or undesirable. It is common and desirable in styles such as Lambic, Oud Bruin, several similarly acidic American-derived styles, and many barrel-aged styles.

Barrel

A unit of measurement equaling 31.5 gallons or two standard kegs.

Whirlpool

A vessel that stirs the wort until a vortex forms, allowing easier removal of the trub.

Diacetyl

A volatile compound produced by some yeasts which imparts a caramel, nutty or butterscotch flavor to beer. This compound is acceptable at low levels.

Maltose

A water soluble, fermentable sugar contained in malt.

Immersion Chiller

A wort chiller most commonly made of copper that is used by submerging into hot wort before fermentation as a method of cooling.

Gruit

An old fashioned herb mixture used for bittering and flavoring beer, popular before the extensive use of hops. _____ ale may also refer to the beverage produced.

Tun

Any large vessel used in brewing.

Dimethyl Sulfide (DMS)

At low levels, DMS can impart a favorable sweet aroma in beer. At higher levels DMS can impart a characteristic aroma and taste of cooked vegetables, such as cooked corn or celery. Low levels are acceptable in and characteristic of some Lager beer styles

Lactobacillus

Bacteria that convert sugar into lactic acid. Some brewers add this intentionally to create a sour flavor in certain styles of beer.

High Gravity Beer

Beer fermented to a high alcohol content, which is then weakened to the desired strength by the addition of water

Lager

Beer produced with bottom fermenting yeast strains at colder fermentation temperatures than ales. The cooler environment inhibits the natural production of esters and other by products, creating a crisper tasting product.

Medicinal

Chemical or phenolic character; can be the result of wild yeast, contact with plastic, or sanitizer residue

Chill Haze

Cloudiness caused by proteins in the beer. Can occur at low temperatures, but does not affect flavor.

Dry

Describes a beer with low levels of malt sweetness; a synonym is "highly attenuated"

Shelf life

Describes the number of days a beer will retain it's peak drinkability. This for commercially produced beers is usually a maximum of four months.

By products

Desirable and undesirable compounds that are a result of fermentation, mashing, and boiling.

Ethanol

Ethyl alcohol, the colorless primary alcohol constituent in beer.

Closed fermentation

Fermentation under closed, anaerobic conditions to minimize the risk of contamination and oxidation

Phenolic

Flavor and aroma of medicine, plastic, Band-aids, smoke, or cloves; cause by wild yeast or bacteria, or sanitizer residue.

Grist

Ground malt and grains for mashing

Pasteurization

Heating of beer to 60-79 C or 140 to 174 F to stabilize it micro biologically. Flash pasteurization is applied very briefly, for 15 to 60 seconds by heating the beer as it passes through the pipe. Alternately, the bottled beer can be passed on a conveyor belt through a heated tunnel. The more gradual process takes at least 20 minutes and sometimes may take longer.

Alpha and Beta Amylase

Important enzmes in brewing beer and liquor made from sugars derived from starch. Different temperatures optimize the activity of alpha and beta amylase, resulting in different mixtures of fermentable and unfermentable sugars.

Musty

Moldy, mildewy character; can be the result of cork or bacterial infection

Beta Acids

One of the primary naturally occurring soft resins in hops. This contributes very little to the bitterness of beer and accounts for some of its preservative quality

Bottom Fermentation

One of the two basic fermentation methods characterized by the tendency of yeast cells to sink to the bottom of the fermentation vessel. Lager yeast is considered to be bottom fermenting compared to ale yeast that is top fermenting. Beers brewed in this fashion are commonly called lagers or bottom-fermented beers.

Top Fermenting Yeast

One of the two types of yeast used in brewing. This yeast works better as warmer temperatures and is able to tolerate higher alcohol concentrations than other type. It is unable to ferment some sugars, and results in a fruitier, sweeter beer. Also known as ale yeast.

Brew Kettle

One of the vessels used in the brewing process in which wort (unfermented beer) is boiled.

Alpha Acid

One of two primary naturally occurring soft resins in hops. These acids are converted during wort boiling to iso-alpha acids, which causes the majority of beer bitterness. During aging, these acids can oxidize (chemical changes) and lessen bitterness.

Aromatic hops

Refers to hop additions that take place later in the boiling process. Shorter amount of time spent in the boil kettle will provide more aromatic characteristics from the hops rather than bittering characteristics.

Bittering Hops

Refers to the hop additions that take place early in the boiling stage of the brewing process. The longer the hops are boiled, the more bittering characteristics the will come from those hops

Lagering

Refers to the maturation for several weeks or months at cold temperatures to settle residual yeast, impart carbonation and make for clean round flavors.

Solventlike

Reminiscent of acetone or lacquer thinner; cause by high fermentation temperatures

Vinous

Reminiscent of wine.

Ale yeast

Saccharomyces cerevisiae is a top fermenting yeast that ferments at warm temperatures (60 to 70 degrees) an generally produces more flavor compounds.

Trub

Sediment formed when proteins and hop resins precipitate out of the wort during boiling and chilling

Winy

Sherrylike flavor; can be caused by warm fermentation or oxidation in very old beer.

Light-struck

Skunklike smell; from exposure to light.

Secondary Fermentation

Stage of fermentation occurring in a closed container for several weeks to several months.

Oxidized

Stale flavor of wet cardboard, paper, rotten pineapple, or sherry, as a result of oxygen as the beer ages or is exposed to light.

Cellaring

Storing or aging beer at a controlled temperature to allow maturing

Cask conditioning

Storing unpasteurized, unfiltered beer for several days in cool cellars of about 48 to 56 degrees while conditioning is completed and carbonation builds.

Fermentable Sugars

Sugars that can be consumed by yeast cells which in turn will produce ethanol alcohol and cO2

Terminal Gravity

Synonym for the final specific gravity

Tart

Taste sensation caused by acidic flavors

Metallic

Tastes tinny, bloodlike or coinlike; may come from bottle caps.

Aeration

The action of introducing air or oxygen to the wort (unfermented beer) at various stages of the brewing process. Properly done before primary fermentation is vital to yeast health and vigorous fermentation. This completed after fermentation is complete can result in beer off flavors, including cardboard or paper aromas due to oxidation.

Fresh hopping

The addition of freshly harvested hops that have not yet been dried to different stages of the brewing process. This hopping adds unique flavors and aromas to beer that are not normally found when using hps that have been dried and processed per usual. Synonymous with wet hopping.

Dry Hopping

The addition of hops late in the brewing process to increase the hop aroma of a finished beer without significantly affecting its bitterness. Dry hops may be added to the wort in the kettle, whirlpool, hop back, or added to beer during or secondary fermentation or even later in the process.

Hopping

The addition of hops to un-fermented wort or fermented beer.

Priming

The addition of sugar at the maturation stage to promote a secondary fermentation

Burton Snatch

The aroma of Sulphur indicating the presence of sulphate ions.

Flocculation

The behavior of suspended particles in wort or beer that tend to clump together in large, masses and settle out. During the brewing, protein and tannin particles will flocculate out of the fermentation, yeast cells will flocclate to varying degrees depending on the yeast strain thereby affecting fermentation as well as filtration of the resulting beer.

Bead

The bubbles in beer, or the cascade of bubbles that rise to the surface.

Malt extract

The condensed wort from a mash, consisting of maltose, dextrins, and other dissolved solids. Either as a syrup or powdered sugar, it is used by brewers, in solutions of water and extract, to reconstitute wort for fermentation.

Body

The consistency, thickness, and mouth filling property of beer. The sensation from the palate fullness ranges from thin to full bodied.

Hot Break

The flocculation of proteins and tannins during wort boiling

Head Retention

The foam stability of a beer measured, in seconds, bu time required for a 1 inch foam to collar to collapse.

Noble Hops

The four traditional European varieties of hops: Hallertauer, Tettnanger, spalt, and saaz. They are generally characterized by an aromatic flavor and low bitterness.

Carbon Dioxide

The gaseous by-product of yeast.

Innoculate

The introduction of a microbe such as yeast of microorganisms such as lactobacillus into surroundings capable of supporting its growth.

attemperation

The method of controlling temperature, usually by running water through pipes to cool hot wort.

Blending

The mixing together of different batches of beer to create a final product

Maillard Reaction

The natural browning that occurs between sugars and protein when food or wort is heated. This happens to roasting malt or beer brewed over an open flame.

Husk

The outer layer of certain cereal seeds

Filtration

The passage of a liquid through a permeable or porous substance to remove solid matter in suspension, often yeast.

Malting

The process by which barley is steeped in water, germinated, then kilned to convert insoluble starch to soluble substances and sugars. The foundation ingredient in beer.

Fining

The process of adding clarifying agents such as isinglass, gelatin, silica gel, or Polyvinyl Polypyrrolidone (PVPP) to beer during the secondary fermentation to hasten the precipitation of suspended matter such as yeast, proteins or tannins.

Carbonation

The process of introducing carbon dioxide into beer.

Attenuation

The reduction in wort specific gravity caused by the yeast consuming wort sugars and converting them into alcohol and carbon dioxide gas through fermentation

Wort

The solution of grain sugars strained from the mash tun.

Final Gravity

The specific gravity of a beer as measured when fermentation is complete (when all desired fermentable sugars have been converted to alcohol and carbon dioxide gas).

Kilning

The step in the malting process of heat drying germinated grain

Brew Kettle

The vessel in which the wort is boiled with hops

Ale

These are fermented with top fermenting yeasts. These beers typically are fermented at warmer temperatures than the other type, and are often served warmer. The term is sometimes incorrectly associated with alcoholic strength.

Barley

This is used as a base malt in the production of beer

Krausen

To add a small amount of partially fermented wort to an already fermented beer, inducing secondary fermentation

Pitch

To add yeast to wort

Mash

To release malt sugars by soaking grain in water. The resultant mixture.

Lauter

To run the wort from the mash tun. The tun uses a system of sharp rakes to achieve a very intensive extraction of malt sugars.

Sparge

To spray grist with hot water in order to remove soluble sugars (maltose). This takes place at the end of the mash.

Heat Exchangers

Used to cool hot wort before fermentation

Esters

Volatile flavor compounds that form through the interaction of organic acids with alcohols during fermentation and contribute to the fruity aroma and flavor of beer. Esters are very common in ales.

Lees

Yeast deposit from secondary fermentation in the bottle

Wort Chiller

heat exchanger

Cold Break

the flocculation of proteins and tannins during wort cooling