Acidic — Having a dry, or sour, taste, especially characteristic of fruity beers.

Additives — Enzymes, preservatives and/or antioxidants that are added to clarify or preserve beer, or to improve head retention.

Adjunct — Fermentable substance used instead of traditional grains to make beer lighter-bodied or cheaper.

Aerobic — Characterizing the type of organism that needs oxygen to thrive. Top-fermenting yeast is an aerobic organism.

Alcohol — Ethyl alcohol or ethanol, which is a by-product of fermentation.

Alcohol by volume — Amount of alcohol in beer expressed as a percentage of total beer volume.

Alcohol by weight — Amount of alcohol in beer expressed as a percentage of beer weight. Due to the specific gravity of beer, this value is typically 20% less than alcohol by volume.

Alcoholic — Warming taste of ethanol and higher alcohol's.

Ale — A type of beer brewed using top-fermenting yeast, which is usually stronger and more bitter than beer. The color can vary from light to dark amber.

All-malt — A beer brewed exclusively with barley malt (i.e., no adjuncts).

Amber — Beer characterized by a reddish-brown color, ranging from pale to dark.

Anaerobic — Characterizing the type of organism that thrives without oxygen. Bottom-fermenting yeast is an anaerobic organism.

Aroma — Another term for bouquet, defined below.

Aroma hops — Varieties of hops chosen to enhance a beer's bouquet; also known as "aristocrat" hops.

Astringent — Having tannic, sour notes, often due to boiling the grains, overly long mashes, or sparging with hard water.

Attenuation — The degree to which the yeast ferments the wort during the brewing process.

Balance — An important tasting concept describing the gestalt of elements in the bouquet and palate of a beer.

Balling Degrees — Scale of the density of sugars in wort, developed by C J N Balling.

Barley — An ancient cereal grain, of which some varieties are used to brew beer. It is first malted, mashed, and then the sugary liquid formed during the mash, called wort, is fermented.

Barrel — A unit of measurement used by brewers in some countries. In Britain, a barrel holds 36 imperial gallons (One imperial gallon equals 4.5 liters), or 1.63 hectoliters. In the United States, a barrel holds 31.5 US gallons (One US gallon = 3.8 liters), or 1.17 hectoliters.

Beer — An alcoholic beverage brewed from barley malt mixed with cultured yeast for fermentation, and seasoned with hops. Popular beer varieties include Ale, Stout, Porter and Lager

Bitter — Having a sharp taste, associated with some hops, known as "workaday" hops. Bitterness is measured in International Bitterness Units (IBU), defined below.

Black malt — Barley that is partially malted and then dried in a kiln at high temperatures to impart a dark color and strong flavor to the beer.

Bock — A strong lager served to warm the drinker during the coldest months of the year; traditionally dark, but color may vary.

Body — A tasting term describing the viscosity of a beer. See also Mouthfeel.

Bottle conditioning — Secondary fermentation and maturation in the bottle, to improve beer complexity.

Bottom-fermenting yeast — One of the two types of yeast (Saccharomyces carlsbergensis) used in brewing, also referred to as "lager" yeast; works well at low temperatures and ferments more sugars for a distinct, clean taste.

Bouquet — A tasting term describing the characteristics of a beer when nosed; may be flowery, fruity, malty, or spicy. Most central to pilsners, but important to all styles.

Brew kettle — The vessel in which the wort from the mash is boiled with hops. Also called a copper.

Brewhouse — The collective equipment used to make beer.

Brewpub — Small brewery attached to a pub or restaurant, typically selling at least fifty percent of its beers on the premises. Also known in Britain as a home-brew house, and in Germany as a house brewery.

Bright — Tasting term describing a beer's color or clarity.

Bright beer tank — See conditioning tank.

Brown Ale — Ranges from dry to sweet in maltiness, often with nutty accents.

Bung — The stopper for the hole of a keg or cask. One measure a beer's authenticity is the use of a wooden bung, which relieves the pressure in the cask during the fermentation process.

Butterscotch — See diacetyl.

CAMRA — The CAMpaign for Real Ale. An organization in England founded in 1971 to support the industry of cask-conditioned beers and ales.

Caramel — A cooked sugar that is used as a beer additive instead of the more expensive malted barley.

Caramel malt — A sweet, reddish-brown malt. The high concentration of unfermentable sugars in caramel malt sweeten the beer and improve head retention.

Carbon Dioxide — A natural by-product of fermentation that gives beer its sparkle, or carbonation. May also be injected artificially into beer.

Cask — A closed, barrel-shaped container for beer. Available in various sizes and usually made of metal.

Cask conditioning — Secondary fermentation and maturation in the cask at the point of sale to create additional carbonation.

Chill haze — Cloudiness caused by precipitation of a protein-tannin compound at low temperatures.

Chill proof — Beer treated to prevent clouding at cold temperatures.

Chlorophenolic — A term used to describe a plastic-like aroma due to the chemical reaction of chlorine with phenol compounds.

Clove-like — A tasting term used to describe the spiciness, especially associated with some wheat beers; in excess it may be due to wild yeast.

Conditioning — Period of maturation that increases a beer's natural carbonation. Warm conditioning enhances the complexity of the flavor; cold conditioning elicits a clear, clean taste.

Conditioning tank — A vessel for conditioning beer, also known as a bright beer tank, serving tank, or secondary tank.

Contract beer — Beer that is marketed by an independent company that represents itself as the brewery.

Copper — See Brew kettle.

Creamy — A tasting term describing the sensation, or mouthfeel, of beer that has good natural carbonation.

Decoction — System of mashing to increase conversion of starches to sugars during which portions of the mash are removed, heated, and then returned to the mash tun.

Dextrin — An unfermentable carbohydrate present in malted barley to varying degree; dextrin content is associated with a beer's palate and mouthfeel. Lower kiln temperatures during malting produce more dextrin and less sugar, while higher temperatures produce less dextrin and more sugars.

Diacetyl — A volatile compound that gives beer a butterscotch flavor, measured in parts per million.

Dimethyl Sulfide (DMS) — A sulfur compound resulting from poor wort processing that imparts a taste and aroma of sweet corn.

Dosage — A measure of yeast and/or sugar added to the cask or bottle to facilitate secondary fermentation.

Draft (Draught) — The process of dispensing beer from a bright tank, cask, or keg. May also be used to describe the carbon dioxide injected into the beer container prior to sealing.

Dry — A tasting term describing a sharp, not sweet palate.

Dryhopping — The addition of dry hops to fermenting or aging beer to increase its hop character or aroma.

Ester — Volatile compound formed during fermentation that gives a beer a fruity, flowery or spicy taste.

Filtration — The removal of impuritiesin the wort or beer. Yeast in suspension is a typical target.

Final specific gravity — See specific gravity.

Fining — A substance to facilitate beer clarification.

Finish — The lingering taste sensation that accompanies swallowing.

Fruity — Tasting term describing the flavor and aroma of bananas, strawberries, apples, and/or citrus notes resulting from high temperature fermentation and top-fermenting yeast strains.

Gravity — See specific gravity.

Grist — Brewers' term for the mix of milled grains to be used in a beer. Also sometimes applied to hops.

Hang — Tasting term used to describe lingering bitterness or harshness.

Hard cider — A fermented beverage made from apples.

Heat Exchanger — A mechanical device for quickly reducing the temperature of the wort.

Hefe — A German word meaning "with" used mostly in conjunction with wheat (weiss) beers to denote that the beer is bottled or kegged with the yeast in suspension (hefe-weiss). These beers are cloudy, frothy, and very refreshing.

Hogshead — Cask holding 54 imperial gallons ( 243 liters ).

Hop back — Sieve-like vessel used to strain out the petals of the hop flowers. Known as a hop jack in the United States.

Hoppy — Having the aroma of hops, but not the bitterness.

Hops — Herbs added to boiling wort or fermenting beer as a seasoning.

IBU — International bitterness units. A system for measuring hop bitterness in finished beer.

Infusion — Simplest method of making mash, in which the malt is soaked in water, typically at a single temperature.

Krusening — The addition of a small amount of partly fermented wort to a brew during lagering for secondary and carbonation.

Malt liquor — A type of beer of relatively high alcohol content (7%-8% by volume), as defined in the United States.

Malting — The process of converting the starches of barley grain to sugars (maltose) in preparation for fermentation. The barley is first soaked in water, germinated, and then kilned.

Maltose — The water-soluble, fermentable malt sugar.

Mash — The malted barley-water mixture whereby the sugars are released, or as a verb, the process of creating this mixture.

Mash tun — A tank for preparing the mash.

Mead — Meads are produced by the fermentation of honey, water, yeast and optional seasonings such as fruit, herbs, and/or spices. They are classified by their final specific gravity as dry, medium, or sweet.

Medicinal — Having a chemical or phenolic taste resulting from wild yeast, contact with plastic, or sanitizer residue.

Metallic — Term associated with over-aged beer.

Microbrewery — Small brewery generally producing less than 15,000 barrels per year. Sales primarily off-premises.

Mouthfeel — A sensation derived from the body or viscosity of a beer, ranging from thin to full.

Musty — Having a moldy, mildewy flavor and aroma, due to cork or brew spoilage.

Oxidized — Characterized by a stale or rotten flavor due to exposure to oxygen or high temperatures during aging.

Pasteurization — Heating of beer to 60-79(¦C/140-174¦F to stabilize it microbiologically. Flash-pasteurization is applied very briefly, for 15-60 seconds by heating the beer as it passes through the pipe, or after bottling, on a conveyor belt through an oven.

Phenolic — Having the flavor and aroma of medicine, plastic, smoke, or cloves, due to wild yeast or bacteria, or sanitizer residue.

Pitch — To add yeast to wort.

Plato, degrees — A refinement of the Balling scale that expresses the specific gravity as the weight of extract in a 100 gram solution at 64¦F (17.5¦C).

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

Pub — Short for a public house, a place that serves beer and sometimes other alcoholic beverages for consumption on the premises.

Publican — The owner or manager of a pub.

Saccharomyces cerevisiae — See Top-fermenting yeast.

Saccharomyces uvarum — See Bottom-fermenting yeast.

Salty — Having a flavor like table salt; experienced on the sides of the tongue.

Secondary fermentation — Fermentation process in a closed cask for additional maturation or carbonation.

Shelf life — The period of time a beer will retain its drinkability. The shelf-life for commercially-produced beers is usually around four months.

Skunky — Having a skunk-like smell, a defect caused by exposure to light; primarily a defect found in beers in clear or green bottles.

Solvent-like — Having characteristics of acetone due to by high fermentation temperatures.

Sour — A term describing an unpleasant vinegar-like or lemon-like taste caused by spoilage.

Sparge — To spray grist with hot water, removing soluble sugars (maltose) at the end of the mash.

Specific gravity — A measure of the density of a liquid or solid compared to that of water ((1.000 at 39¦F (4¦C)). The original specific gravity of a beer is measured before fermentation, and the final specific gravity is measured after fermentation is completed.

Squares — Brewers' term for a square fermenting vessel.

Sulfurlike — Term describing an unpleasant taste or aroma of rotten eggs due to a sulfur compound produced by some yeast strains.

Sweet — Having a sugary taste; experienced on the front of the tongue.

Tart — Taste sensation cause by acidic flavors.

Terminal gravity — Synonym for final specific gravity.

Top-fermenting yeast — One of the two types of yeast (Saccharomyces cerevisiae) used in brewing, also referred to as "ale" yeast; works well at warmer temperatures, able to tolerate higher alcohol concentrations, and ferments fewer sugars for a fruitier, sweeter taste.

Tun — Any large vessel used in brewing. In America, the term "tub" is more commonly used.

Wort — The solution of grain sugars strained from the mash tun. At this stage, regarded as "sweet wort", later as brewed wort, fermenting wort and finally beer.

Wort Chiller — See heat exchanger.

Yeasty — Having a yeast-like flavor resulting from yeast in suspension, or beer sitting too long on sediment.