Beer Terminology

AAU

Alpha Acid Unit, or AAU, is a measurement for bitterness in a given hop flower. The higher the percentage, the more bitter the yield.

ABV

Alcohol by Volume given as a percentage. Measures the amount of ethanol in a liquid. It is a common measurement used around the world (ABW is also used to express the mass of alcohol in beverage).

Adjunct

Unmalted grains or additional ingredients that are added in brewing. Most common products are corn, rice, wheat and sugar.

Aeration

The introduction of oxygen into wort to allow for proper yeast production.

Airlock

A device used to seal a fermentation vessel. Keeps unsanitary air out, while allowing CO2 to escape.

Alcohol

The substance that results from yeast feasting on the sugars in the malt during fermentation. The yeasts eat up the fermentable sugars creating two byproducts: ethanol (alcohol) and carbon dioxide. The more fermentable sugar available, the higher the alcohol content. Commonly known to have intoxicating effects.

Ale

A common term for beer that denotes what type of yeast is used. Generally, more fruity in flavor and fermented at warmer temperatures (55°-75°F). Think of ale as a “hot brewed” solution, like tea.

Ale yeast

A strain of yeast that works towards the top layer of liquid giving it the term “top-fermenting yeast.” It likes to operate at warmer temps between 55-70°F.

Attenuation

The measurement of the amount of sugars remaining (or amount of sugars consumed) in the beer after fermentation process. Takes into effect the starting gravity vs. the final gravity.

Balling

A measurement comparing the density of a liquid to that of water.

Barley

Grain that is used as the primary source of sugars in a beer upon malting.

Beer

A malt beverage made from grains, most often fermented.

Beta acids

Insoluble resins found in the hop flower. Attributes to minor bitterness.

Bittering hops

Hops added specifically for their bittering qualities during the boiling stage.

Boiling

One of the key steps in making beer. Used to break down complex sugars into simple sugars for the yeast to feed off of. Hops are also added during this process to break down bittering resins.

Body

The feeling of the beer in your mouth as it pertains to fullness. There are light-bodied beers, like anything considered “light”, medium-bodied, and full-bodied beers like some stouts, IPAs, Double IPAs, etc. Relative to how thick or thin the beer feels in your mouth.

Bottle conditioning

A method of obtaining carbonation in a beer by means of active yeast feeding on sugars while inside the bottle.

Brettanomyces

A yeast strain that produces funky, sour, and wild flavored beers.

Brussels lace

Foam left on the sides of the glass. See also: lacing.

Carbonation

The bubbles you see in beer. CO2 that is forced/dissolved into the liquid. Carbonation as CO2 is achieved as a byproduct when yeast breaks down sugar.

Carboy

A large glass container used by most homebrewers for fermenting or lagering. Can come in a range of sizes, but 5 gals is standard.

Cask

A barrel made from wood that is used to transport and serve beer.

Conditioning

The process in which a beer obtains carbonation. Can happen naturally from the yeast giving off CO2 in an enclosed container like a bottle or keg, or can be forced using pressurized CO2. Also pertains to aging a beer over time to fully develop flavors and alcohol content.

Dry hopping

Adding hops to the beer during the fermentation process in order to increase the aroma. Generally done after the boiling phase, when the beer is in a secondary vessel.

Extract

Wort that has been dehydrated into a syrup or powder. Used most often by homebrewers.

Fermentation vessel (FV)

A large, sterile container where fermentation takes place.

Final gravity

The last gravity reading taken after fermentation is complete to calculate the density of the beer to that of water.

Finishing hops

Hops added during the final minutes of the boil, helping to impart more aroma.

Firkin

A British cask that is equal to 10.8 US gals.

Flocculation

When yeast join together after being suspended in the liquid to form sediment.

Germination

When a kernel of grain begins to sprout new growth. This means the grain loaded with enzymes and starches that are useful to brewers.

Gravity

The weight of a liquid relative to the weight of an equal volume of water. This is a basic scientific measurement used to determine the alcohol content of a beer. Specific gravity is measured before and after fermentation with a device called a hydrometer. The result of a mathematical equation between those 2 numbers give you your alcohol content, or ABV.

Grist

Crushed grains.

Grits

Crushed adjunct grains like corn or rice.

Hops

One of the four basic ingredients in beer. A cone shaped flower used to create bitterness, aroma, and also serve as a preservative. Hops have many different flavor profile characteristics, ranging from citrus-y, to piney, to earthy. The wide range of varieties available provide ample opportunities to create many diverse flavors and aromas in beer. Only the female vine is sought after.

Hydrometer

An instrument used to measure the gravity, balling, and estimated alcohol content in a given liquid.

IBU

International Bitterness Unit (IBU) is a brewing industry standard for determining how bitter a beer will be given the hops AAU percentage and the length of boiling. The higher the IBU number, the more bitter the beer.

Keg

A metal vessel used to hold and dispense carbonated beer.

Kettle

The large vat where the wort is boiled. Often referred to as a “copper”.

Kiln

A dry oven used to dry out grains that have germinated. Can be done in a variety of roasting techniques (just like coffee beans).

Kraüsen

Pronounced “KROY-zen”. German name for the yeasty foam atop the beer during the fermentation process.

Lacing

Term referring to the foam left on the inside of the beer glass. See also: Brussels lace.

Lager

German word meaning “to store”. A very common style of beer. As opposed to an ale, it is generally fermented at lower temperatures (32°-50°F) and is slow working at the base of the liquid. Hence, the “bottom-fermenting” term given to it. The flavor is usually crisp and clean. Think of a lager as “cold brewed”.

Lautering

The act of separating grains from liquid during the initial brewing stages. A large circular disc with small holes in it acts as a strainer and sits above the actual base, allowing the liquid to drain (known as a “false bottom”).

Lauter tun

A traditional vessel used for lautering.

Liquor

Contrary to popular misconception, liquor it is not the alcohol, but rather the water used to make it.

Lovibond (°L)

A European measurement for the color found in beer or kilned grains. See also: SRM.

Lupulin

The yellowish resin found under the petals of hop flowers. This is where the bitterness comes from when they are broken down during the boil.

Malts

One of the four key ingredients in beer. Grains that have germinated and then kilned and are ready for brewing.

Mash

The combination of malt and hot water (liquor) which begins breaking down the sugars and starches created during the germination process.

Original gravity

The first gravity measurement taken before fermentation to determine density. Will be compared with the final gravity measurement to calculate how much sugar has been converted.

Pasteurization

The process of sterilizing beer through the use of heat. Named for its inventor, Louis Pasteur.

Pitching

Refers to the adding of yeast to the unfermented wort. Brewers usually “pitch the yeast” once the wort has cooled after the boil and been transferred to a secondary container.

Plato (°P)

A measurement of the strenghth of beer meaured in degrees (degrees Plato). More descriptive that specific gravity, because it expresses the amount of fermentable materials present.

Primary

A term used for a fermentation vessel that is used for the initial fermentation process before the beer is transferred to a secondary vessel.

Priming

Adding sugar to a beer in order to reactivate any remaining yeast cells before bottling. This is done to produce further carbonation.

Racking

Transferring beer from one place to another.

Secondary

Another fermentation vessel used to lager, mature, clear, or dry-hop a beer. Beer is moved out of primary and into secondary.

Sparging

A means of rinsing the grains after they have been soaking in the mash. This is done during the lautering phase.

SRM

Standard Reference Method. An American measurement in the color of beer and grains. See also: Lovibond.

Steeping

The process of allowing grains, hops, or other ingredients to soak in hot water.

Trub

Pronounced “TROOB”. Proteins and hop oils that collect in the wort during the boil. Often times removed.

Wort

The liquid that contains sugars before the yeast is added (unfermented beer). Liquid is first considered “wort” during the boil.

Yeast

A single-celled fungi that feeds on sugar and oxygen, and produces ethanol (alcohol) and CO2. The two main types of yeast used in brewing are Saccharomyces uvarum (lager yeast) and Saccharomyces cerevisiae (ale yeast).

Zymergy

The study of the fermentation process.