Acetaldehyde

A chemical compound found in beers and wines which has a fruity aroma. Excess Acetaldehyde can be caused by racking the beer soon.

Acetification

The process in which acetic bacteria convert alcohol into acetic acid (vinegar) and ethyl acetate.

Adjunct

Unmalted grains like barley, corn, oats, rice, rye, and wheat or Sugars such as brown sugar, corn sugar and belgian candy sugar which are added to the main mash ingredients, such as malted barley, to add a specific quality such as a particular or colour or flavour, head retention or body to the beer.

Aerobic

A process which requires or occurs in the presence of oxygen.

Alcohol

Ethyl alcohol or ethanol is a colourless liquid produced by the fermentation of sugar.

Alcohol by Volume

The alcohol content expressed as a proportion of the total volume of liquid.

Alcohol by weight

The alcohol content expressed as a percentage of the total weight of liquid. As alcohol weighs less than water this figure is approximately 20% less than alcohol by volume.

Alcoholic

A warming taste or aroma due to an abundance of alcohol

Ale

Beers brewed using top fermenting yeast which performs at higher temperatures imparting a fruitier, full bodied taste.

All Grain

Method of brewing using grains rather than extracts to produce wort.

All-malt

Beer brewed without the use of adjuncts.

Amber Ale

An American term sometimes used to define Ales which are slightly darker than average American Pale Ales.

Anaerobic

A process which occurs in the absence of oxygen.

Aroma Hops

Hops added at or near the end of the boil to add aroma to the beer, they contribute little or no bitterness to the beer.

Aspirator

See Cask Breather

Astringent

A sharp drying taste caused by tannins. Can be caused by over sparging.

Attenuation

Attenuation is the percentage of sugars that yeast consume during fermentation. For beer an apparent attnuation of 75% is expected.

Balling Degrees

Percentage by weight of dissolved solids in a liquid. (See also - Plato Degrees)

Barley

Grain (usually malted) which makes up the majority of the grist in the mashing process.

Barrel

A Barrel is a unit of measure equal to 36 Imperial Gallons in the UK or 31.5 US Gallons in the US.

Beer

Technically, wort becomes beer after yeast has been pitched. There are 3 main types of beer - Lager, Ale, and Specialty Beers.

Bitter

Bitter is a type of lighty carbonated Pale Ale of a golden or copper colour. Bitter falls into 3 categories - Ordinary Bitter which is usually 4% ABV or less, Best bitter at around 4% to 4.8% and Strong bitters usually at greater than 4.8% though each brewery uses its own guidelines.

Bitterness

Bitterness in beer is Measured in IBUs (International Bittering Units).

Black Malt

Black Malt is Malted Barley that has been roasted at very high temperatures (@200°c) . It is used mainly to providea Dark colour and Smokey flavour. This is also called Patent Malt or Black Patent Malt because its inventor was awarded a patent on it.

Black Patent Malt

See Black Malt

Boiler

See Copper

Bottle-conditioning

When Secondary Fermentation and Maturation take place after bottling. This is evident by the presence of a thin layer of yeast at the bottom of the bottle.

Bottom Fermenting Yeast

Type of yeast which ferments at temperatures between 7°c and 15°c. It doesn’t actually work at the bottom of the fermenting vessel but is dispersed throughout the brew. The term bottom fermenting refers to the fact that it doesn’t form as much foam at the surface as Top fermenting yeasts.

Brew Kettle

See Copper

Brewhouse

Location where brewing equipment is housed in a brewery.

Copper

This is the container you boil the wort in. Also refered to as a Brew Kettle or Boiler.

Copper hops

These are the hops added to the wort in the copper at the beginning of the boil. Their job is mainly to add bitterness to the beer

Extract Brewing

Method of brewing Using Malt Extract

HBUs

A calculation used by home brewers to estimate the bitterness of their brews based on the Alpha Acid Units of the Hops. This is similar to IBUs.

IBU

A measurement of the bitterness of a beer. For Home Brewing see HBUs

Liquor

Term used for the water used in brewing.

Malt Extract

Canned concentrated wort used in Extract Brewing.

Mash Tun

A container (usually insulated) used to steep (mash) grains to extract the sugars contained in the grain.

Mashing

The process of steeping grains in water at a predetermined temperature to allow enzymes in the grains to convert starches into fermentable sugar.

Pitch

To add yeast to wort

Wort

This is the term used for the brewing liquid after mashing is complete but before yeast is pitched. Once yeat is pitched it is technically beer.