Beer Term Glossary | BeverageFactory.com

Acid Cleaner

Although several blends of acid cleaners are recommended to assist in beer stone and water stone removal, some acids react with system components. Phosphoric acid-based blends are the only ones safe on all materials.

Adjunct

Any non-enzymatic fermentable used as a substitute to traditional grains to reduce cost and produce lighter-bodied, paler, and less malty beers. Common adjuncts include unmalted grains such as flaked barley, rice, corn, maize, and oats, and can also include fermentable carbohydrates like honey, syrups, and refined sugars.

Aerate

Introducing air to cooled wort at various stages of the brewing process. Aeration prior to primary fermentation is vital to maintaining healthy yeast, while aeration after fermentation can lead to off-flavors due to oxidation.

Ale

A beer brewed from a top-fermenting yeast (Saccharomyces cerevisiae) with a relatively short, warm fermentation between 65-75 degrees Fahrenheit. Ales often feature a fruity or estery nose or flavor.

All-Extract Beer

A beer made with malt extract as opposed to one made from malted barley or from a combination of malt extract and malted barley.

All-Grain Beer

A beer made with malted barley as opposed to one made from malt extract or from malt extract and malted barley.

All-Malt Beer

A beer made exclusively with barley malt, with no adjuncts, refined sugars, or additional fermentables.

Alpha Acid Units (AAU)

A homebrewing measurement of hop bitterness. It is equal to the percentage of alpha acids of the hops multiplied by the weight of hops used (in ounces). Because the AAU formula does not consider factors like wort gravity, boil time, and batch size, the International Bitterness Units (IBU) formula is mainly used instead.

Attenuation

A percentage that measures the extent to which the yeast has consumed the fermentable sugars and converted them into alcohol and CO₂. More attenuated beers are generally drier and have a higher ABV% than less attenuated beers, even if they have been made from the same wort.

Balance

A beer system is considered to be in balance when the applied pressure equals the restriction so that the beer dispenses at an optimum flow rate of approximately 2 ounces per second or 1 gallon per minute while maintaining the brewery-specified carbonation level.

Barrier Tubing

Plastic tubing with a lining of nylon or PET that provides a gas barrier to better protect the beer from oxidation.

Beer

The name given to any beverage produced by fermenting a wort made from grain (specifically malted barley) and seasoned with hops.

Beer Pump

A mechanical pump that is generally driven be compressed air or CO₂ that can move beer great distances without changing the dissolved gases. It is used when the keg is far away from the faucet.

Beer Stone (Calcium Oxalate)

A mineral deposit composed of calcium oxalate, protein, and sugar that forms slowly on a surface from beer and is very difficult to remove. It tends to accumulate when brewing and dispensing equipment is used repeatedly without proper cleaning. If the beerstone is not completely removed, it can lead to unsanitary conditions that can harbor microorganisms.

Blow-off

A type of airlock arrangement consisting of a tube exiting from the fermenter, submerging into a bucket of water, that allows the release of carbon dioxide and removal of excess fermentation material.

Carbonation

Carbonation is the "fizz" in beer, which is generally created during fermentation by yeast eating fermentable sugars and releasing carbon dioxide in a sealed container. Beer can also be carbonated by injecting the finished beer with carbon dioxide, adding young fermenting beer to finished beer for a renewed fermentation (kraeusening), priming (adding sugar to) fermented wort prior to bottling to create a secondary fermentation in the bottle (Known as "bottle conditioning "), or by finishing fermentation under pressure.

Carboy

Carboys are large glass, plastic, or earthenware bottles that are popular fermentation vessels.

Caustic, Caustic Soda, or NaOH (Sodium Hydroxide)

A high pH chemical commonly used in blending draught line cleaning solutions that will react with organic deposits in the draught beer line. Very effective, but also very dangerous. Commonly used in oven cleaners.

Caustic Potash or KOH (Potassium Hydroxide)

Similar to sodium hydroxide, but offers slightly different chemical properties in a blended cleaning solution.

Closed Fermentation

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

CO₂

Carbon dioxide is a natural product of fermentation. In draught beer systems where the faucet and keg are close together, CO₂ is also used to push the beer from the keg through the beer line to the faucet. CO₂ leaks in the gas system are dangerous because high concentrations of CO₂ will displace air and cause asphyxiation.

Coil Box

A coil box (also known as a jockey box) is a cooling system consisting of a coil of stainless steel immersed in ice water that brings beer down to serving temperature at the point of dispense. It is often used at picnics and special events where normal keg temperature cannot be maintained.

Conditioning

A term for secondary fermentation in which the yeast refine the flavors of the beer. Conditioning continues in the bottle as long as there are active yeast present. Also, conditioning refers to the level of carbonation and the quality of mouthfeel of a beer during judging.

Coupler

A coupler is a device that is attached to the top of a keg to connect the gas line and the beer line to the keg. It opens the valve in the keg to allow gas in through the gas line and push beer out through the beer line. There are several different coupler styles available for use with the different styles of keg valves. Most domestic U.S. brewing companies use the "D" system keg coupler.

Dewar

An insulated, pressurized container for liquefied gas such as CO₂.

Direct Draw

A draught beer system with self-contained keg storage and a dispense setup that connects the keg to the faucet using a short jumper connection. This type of dispense system is generally air-cooled and dispenses beer through lines five feet long or shorter.

Decoction

A method of mashing whereby temperature rests are achieved by removing a portion of the mash, boiling it, and then returning it to the mash tun to boost the mash temperature.

Dry Hopping

The addition of hops to fermenting or aging beer in order to add aroma and hop character without adding significant bitterness. These hops can be added to cooled wort in the kettle, to the primary or secondary fermenter, or even to finished beer in the cask or keg.

EDTA (Ethylene Diamine Tetracetic Acid)

A cleaning solution additive that can dissolve calcium mineral deposits in draught beer systems.

Esters

"Ethereal salts" such as ethyl acetate; aromatic compounds from fermentation composed of an acid and an alcohol, such as the "banana" ester. Formed by yeast enzymes from an alcohol and an acid. Associated with ale and high-temperature fermentations, although esters also arise to some extent with pure lager yeast cultures, though more so with low wort oxygenation, high initial fermentation temperatures, and high-gravity wort. Top-fermenting yeast strains are prized for their ability to produce particular mixes of esters.

Extract

The soluble constituents left over after mashing and lautering malted barley, including sugars and proteins. The liquid is removed and the sweet wort is reduced to a syrup or a powder that can be easily used by homebrewers.

Extraction

Drawing out the soluble essence of the malt or hops.

Faucet

A beer faucet is a device attached to a beer tower or beer shank through which beer is poured into a glass (the point of dispense). A standard American style faucet is opened with a quick one step pull to allow the beer to flow and closed with a push to stop the flow. European faucets often have a flow control knob for adjusting the flow rate of the beer at the faucet. If you are dispensing beer using nitrogen, you will need a stout faucet with a restrictor disc.

Fermentation

The total conversion of fermentable malt sugars into ethyl alcohol and carbon dioxide through yeast. Top fermentation produces ales while bottom fermentation produces lagers. Primary fermentation can take place in open or closed vessels, and a secondary fermentation may take place in a cask, keg, or bottle.

Fermentation Lock

A fermentation lock (also known as an airlock) is a one-way valve made of glass or plastic that allows carbon dioxide gas to escape from the fermenter while preventing the entry of bacteria and other contaminants.

Final Specific Gravity

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

Finings

Finings are ingredients such as isinglass, bentonite, Irish moss, silica gel, Polyclar, and geletain that are added during secondary fermentation to improve clarity by helping the yeast, suspended proteins, and polyphenols to flocculate and settle out of the beer.

Flash Chillers

Flash chillers are mechanical cooling systems that are used to bring beer to serving temperature at the point of dispense. They are often used with flash-pasteurized kegs that can be stored at room temperature.

Flocculation

The tendency of yeast to clump together, gather, or fallout at the end of fermentation. Different yeast strains have different tendencies to flocculate. The greater the tendency for the yeast to flocculate, the faster it will drop out of the solution, creating clear beer.

FOB

The acronym for a "foam on beer" detector. This is a device that prevents a pour full of foam by stopping the flow of beer as soon as foam is detected and beer is not.

Glycol or Propylene Glycol

Glycol or Propylene Glycol is a food-grade refrigerant that is recirculated through insulated tubing bundles to keep beer cold.

Gravity

Like density, gravity describes the concentration of malt sugar in the wort. The specific gravity of water is 1.000 at 59 degrees Fahrenheit. Typical beer worts range from 1.035-1.055 before fermentation. The gravity of the beer before fermentation is referred to as original gravity (OG), while the gravity of the beer after fermentation is referred to as final gravity (FG).

Gravity Units (GU)

A form of expressing specific gravity in formulas as a whole number. It is equal to the significant digits to the right of the decimal point (1.055 SG becomes 55 GU and 1.108 SG becomes 108 GU).

Grist

The term for the crushed malt and adjuncts that will be mixed with hot water for mashing.

Hopback

A hopback is a sieve-like vessel that is filled with hops to act as a filter for removing the break material from the finished wort. Also known as a hop jack.

Hops

Brewers add the cone-like flowers of the Humulus Lupulus hop plant to boiling wort or fermenting beer to give beer its bitter aroma and flavor and inhibit the growth of bacteria. The dried cones are available in pellets, plugs, or whole. Hops can be added at the beginning of the boil (bittering hops), the middle (flavoring hops), the end (aroma hops), or later in the brewing process (dry hops).

Hop Pellets

Finely powdered hop cones compressed into pellets. Hop pellets are less subject to alpha acid losses than are whole hops.

Hydrometer

An instrument that is used to measure the specific gravity (SG) of beer compared to water in order to help you monitor the fermentation process. A common glass hydrometer consists of a graduated stem resting on a weighted float, which is lowered into a wort sample until it floats freely. The point at which the surface of the liquid touches the hydrometer stem indicates the specific gravity.

International Bitterness Units (IBU)

A more precise method of measuring hop bitterness. The formula is the weight of hops (in ounces) X alpha acid percentage X percentage of alpha acids used in boiling process / volume of wort (in gallons) X 1.34. The IBU measurement will vary depending on the style of beer, with a higher IBU indicating a more bitter beer.

Irish Moss

An emulsifying agent, Irish moss promotes break material formation and precipitation during the boil and upon cooling. Irish moss is sold as dehydrated flakes and should be rehydrated before use. Use by adding it to the boil during the last 15 minutes. Recommended dose (as flakes) is 2-3 tsp/5 gallons, or 1/16-1/8 grams per liter.

ISBT

International Society of Beverage Technologists, who created a quality standard for CO₂ for beverage use.

Jockey Box

A jockey box is a picnic cooler or ice chest that has been converted into a beer dispenser using either a cold plate or a stainless steel coil to chill the beer. When using a cold plate, the plate should be tilted, and the box should be continuously drained of water. When using a coil, a mixture of ice and water must completely cover the coils in the cooler. Cubed ice should be used in this type of box, and the CO₂ regulator should be set between 30 and 40 lbs of applied pressure.

John Guest Fittings

A specific brand of quick connect for stiff plastic tubing.

Jumper Tubing

The flexible piece of vinyl tubing used between the keg and draught beer system that should be replaced annually.

Kraeusen

The period of fermentation characterized by a rich foam head. Kraeusening describes the addition of actively fermenting beer to fully fermented beer in order to induce a secondary fermentation and create natural carbonation.

Lag Time

The period of adaptation and rapid aerobic growth of yeast upon pitching to the wort. The lag time typically lasts from 2 to 12 hours.

Lager

A beer brewed from a bottom-fermenting yeast called Saccharomyces uvarum (or carlsbergensis) and given a long cool fermentation (generally between 45-55 degrees Fahrenheit). Lager beer is characterized by a lack of esters, a maltier flavor, and high clarity. Lagering refers to aging beer at cold-storage temperatures, and comes from the German word "lagern" which means "to store".

Lauter

Lautering is the process of separating mash into the clear liquid wort and the residual grain. It comes from the German adjective for "pure".

Lauter Tun

A large vessel in which the mash settles and the grains are removed from the sweet wort through a straining process known as "lautering". It generally has a false, slotted bottom and a drain spigot.

Lift

The change in height from the keg to the faucet that is a component of system balance.

Line

Beer line is used to connect the keg coupler to the faucet. It comes in a variety of sizes, colors, and materials. The most common beer line materials are stainless steel, vinyl, polyethylene, and barrier. Vinyl line is generally used in jockey boxes or direct draw systems, stainless steel is generally used in draft towers or special event coolers, and barrier and polyethylene are generally used in glycol systems. Gas line is used to connect the primary regulator to the secondary regulator, the blender, or the CO₂ inlet of the keg coupler. It is available in a variety of materials such as vinyl or braided vinyl, with a selection of colors and sizes. Red is usually used for lines with less than 50 lbs of pressure, while braided is used for systems that require more than 50 lbs of applied pressure.

Long Draw

A draught beer system over 50 feet long that uses barrier tubing in a refrigerated bundle that typically requires a mixed gas to avoid overcarbonation. This type of system is generally used in restaurants, bars, and tasting rooms that store multiple kegs in a separate refrigerated room from the point of dispense.

Lovibond

A unit of malt color measurement, based on standard solutions. The higher the number, the darker the malt. The scale goes from 0 to over 500. The low end (<35) is equivalent to the Standard Reference Method (SRM) for all practical purposes.

Maillard Reaction

A browning reaction caused by external heat wherein a sugar (glucose) and an amino acid form a complex, and this product has a role in various subsequent reactions that yield pigments and melanoidins.

Malt

Malt - one of the main ingredients in beer - is barley or other grains that have been steeped in water, germinated, then dried in kilns. The malting process converts insoluble starches to soluble substances and sugars. Malt flavor can be influenced by the type of grain used, the level of fermentation, and the drying temperature.

Malt Extract

Malt extract is sweet wort that has been reduced to a thick syrupy liquid or a dry powder. Malt extract brewing can be a great choice for new homebrewers, as it requires less time and equipment than all-grain brewing.

Maltose

A water soluble, fermentable sugar contained in malt. The preferred food of brewing yeast, maltose consists of two glucose molecules joined by a 1-4 carbon bond.

Maltotriose

A sugar molecule made of three glucoses joined by 1-4 carbon bonds.

Mash

The process of mixing milled grains ("grist") with water and then boiling it to promote the enzymatic breakdown of the grist into soluble, fermentable sugars. Mashing results in a malty liquid called "wort".

Melanoidins

Color-producing compounds produced through a long series of chemical reactions that begin with the combination of a sugar and an amino acid.

Nitrogen Generator

An on-site device used to produce nitrogen gas by filtering the nitrogen from compressed air. It is typically used in high volume accounts to reduce costs associated with refilling nitrogen tanks, or when changing tanks can be a burden. Nitrogen used for beer dispense in a mixed gas application must be >99% pure.

NSF (National Sanitation Foundation)

An organization that certifies food service equipment for performance and cleanability.

Original Gravity (OG)

The specific gravity of wort before the yeast has been added, prior to fermentation. It is a measure of the total amount of dissolved solids in wort in comparison to the density of pure water at a certain temperature (which has the value of 1.000 SG).

Party Pump or Picnic Pump

A party pump is a manual hand pump (typically used at parties or special events) that uses compressed air to dispense beer instead of CO₂ gas. When using a party pump, you should always remember to keep the beer cold to prevent it from warming up and causing foaming. You should only use this type of pump if the beer will be consumed in 8 to 12 hours, as the beer will spoil much more quickly than beer dispensed from a kegerator using CO₂.

PE (Polyethylene)

Stiffer tubing used in older refrigerated bundles (this oxygen-permeable material contributed to oxidation of the beer remaining in the lines and is now only recommended for use as glycol tubing).

pH

The abbreviation for "potential hydrogen". This is a negative logarithmic scale (1-14) that measures the degree of acidity or alkalinity of a solution for which a value of 7 represents neutrality. A value of 1 is the most acidic, while a value of 14 is the most alkaline.

Pitching

Inoculating sterile wort with a vigorous yeast culture. Ale yeast is usually pitched under 75 degrees Fahrenheit and above 65 degrees Fahrenheit, as pitching when the wort is too cold can slow fermentation while pitching when the wort is too warm can kill the yeast.

Plato, degrees

Commercial brewers' standard for the measurement of the density of solutions, expressed as the equivalent weight of cane sugar in solution (calibrated on grams of sucrose per 100 grams of solution). Like degrees Balling, but Plato's computations are more exact.

Pot (Pressure Pot or Cleaning Pot)

A pressure pot or cleaning pot is used to clean draft dispensing components. It consists of a canister that is filled with cleaning solution or rinse water and then tapped like a keg. It is connected to a pressure source and pushes the solution through the lines like beer. This system does not give sufficient velocity for (mechanical) cleaning, so it should only be used on short lines with longer chemical exposure.

ppm

The abbreviation for parts per million and equivalent to milligrams per liter (mg/l). Most commonly used to express dissolved mineral concentrations in water.

Primary Fermentation

The vigorous fermentation phase where yeast cells multiply and feed on fermentable sugars in the wort, converting them into ethyl alcohol and carbon dioxide. Most of the total attenuation occurs during this first stage of fermentation.

Priming

The method of adding a small amount of fermentable priming sugar prior to racking or bottling to induce a secondary fermentation and give the beer carbonation.

Priming Solution

A solution of sugar in water added to aged beer at bottling to induce fermentation (bottle conditioning).

Priming Sugar

Priming sugar is the small amount of corn, malt, or cane sugar added to bulk beer prior to racking or at bottling to induce a new fermentation and create carbonation.

PSI

Pounds per square inch. A unit of measure of gas pressure.

PSIA

Pounds per square inch, absolute. A measure of gas pressure against a perfect vacuum so it includes the atmospheric pressure of 14.7 psi at sea level.

PSIG

Pounds per square inch, gauge. A measure of gas pressure against the atmospheric pressure, typically seen on gas regulator gauges. Since atmospheric pressure varies with altitude, the gauge pressure must be adjusted with altitude.

PVC (Polyvinyl Chloride)

Industry standard beer line is made from PVC, a low cost alternative to stainless steel or barrier line. The Brewers Association recommends that PVC lines be changed annually.

Racking

The transfer of beer or wort from one vessel to another. This can be done with a racking cane like the auto-siphon or standard racking cane.

Real Ale

A style of beer found primarily in England, where it has been championed by the consumer rights group called the Campaign for Real Ale (CAMRA). Generally defined as beers that have been cask-conditioned in the cellar, undergoing a secondary fermentation in the container from which they are served. They are usually dispensed from the cask using a gravity dispense tap or a beer engine without additional nitrogen or carbon dioxide pressure.

Regulator

A gas control valve that delivers a set gas pressure regardless of tank pressure. There may be a primary regulator on the gas source and a secondary regulator at the gas connection for each keg. The primary CO₂ regulator attaches to the gas source, a bottle, or a bulk tank and is used to decrease the tank's high gas pressure to a lower pressure. A primary regulator may be adjusted to the ideal gauge pressure and connected by gas line directly to a keg coupler, or may be installed to provide gas pressure to a secondary CO₂ regulator. It utilizes a female connector in order to connect to the gas source. A primary nitrogen regulator is similar to a CO₂ regulator but is used for nitrogen gas. It utilizes a male connector to connect to the source of the nitrogen. A secondary regulator is a regulator not connected directly to the gas source and is normally located in the cooler. Typically, the secondary regulator is installed between the primary regulator and a keg coupler to enable the ideal gauge pressure to be set for individual beer kegs.

Resistance (or System/Component/Line Resistance)

The resistance beer encounters as it flows from a keg, through the tap, beer line, and other hardware designed into a beer dispensing system. Restriction in a beer system comes from the type of beer line used and the size and length of that line, the gravity (lift or drop) in the system, the altitude at which the beer is dispensed, and the components used in the beer system.

Rest

Mash rest. Holding the mash at a specific temperature to induce certain enzymatic changes.

Saccharometer

An instrument that determines the sugar concentration of a solution by measuring the specific gravity.

Sanitize

To reduce microbial contaminants to insignificant levels.

Sanitizer

Sanitizers are EPA-registered products designed to kill harmful microorganisms. Any dispensing components that come into contact with beer must be sanitized.

Sankey

A Sankey coupler is the modern style of keg coupler, and is available in several versions to fit specific styles of keg valves produced in Europe and the United States. The American Sankey coupler (also called a D system coupler) is the coupler used by most U.S. brewing companies.

Secondary Fermentation

The second, slower stage of fermentation that takes place in a closed container after primary fermentation and before bottling. It can occur over several weeks or several months depending on the type of beer. Also refers to the renewed fermentation in bottles or casks that is initiated by the addition of priming solution or fresh yeast.

Sequestrants

Chemicals that hold metal ions in solution and prevent mineral deposits.

Series Kegs

Hooking multiple kegs together so the beer from the first flows through the second and then into the next so that the kegs can be changed less frequently.

Shank

A shank is the connecting piece that goes through a cold box wall or tower to connect the beer line and the tail piece to the faucet. It can also help provide system pressure reduction. Shanks are generally made of brass or stainless steel and come in a wide variety of sizes.

Short Draw

A draught system under 50 feet long in which the keg and the faucet are fairly close together. It uses straight CO₂ or mixed gas to push beer through the lines, and can use air-cooled or refrigerated lines to keep the beer cool.

Sparge

The even distribution or spray of water over the saccharified mash to recover the remaining soluble sugars from the spent grains at the end of the mash.

Sparging

In lautering, the process of spraying the spent grains in the mash with hot water to retrieve the remaining liquid malt sugar and extract in the grain husks.

Specific Gravity

The measure of the density of a solution (in grams per milliliter) compared to that of water, which has a specific gravity of 1.000 at 39 degrees Fahrenheit (4 degrees Celsius). It has no units and is expressed as a ratio. This measurement is highly useful for monitoring various stages of the brewing process.

Starch

A polymer of sugar molecules, starch is the chief form of energy storage for most plants. It is from starch that the relevant sugars for brewing are derived.

Starter

A batch of fermenting yeast, added to the wort to initiate fermentation.

Steeping

The initial processing step in malting where the raw barley is soaked in water and periodically aerated in order to induce germination.

Sterilize

To eliminate all forms of life, especially microorganisms, either by chemical or physical means.

Strike Temperature

The target temperature of a mash rest, the temperature at which a desired reaction occurs.

Surfactants

Compounds used in blended draught beer line cleaners that lower surface tension to enhance surface wetting, break the bond between deposits and the tubing surface, and suspend soils in cleaning solution so they can be removed.

Tail Pieces

Tail pieces are the connectors that allow a piece of tubing to be attached to a piece of equipment, such as a beer faucet.

Tannins

Astringent large polyphenol compounds that can cause haze and/or join with large proteins to precipitate haze from solution. Tannins are most commonly found in the grain husks and hop cone material.

Tap

The device attached to a keg or cask to connect the air line and beer line from the draught system to the keg (typically referred to as a coupler).

Tavern Head

Connects the air line and the beer line from the draught system to the keg (more commonly referred to as a coupler).

Tower

The draft beer tower is the unit typically mounted on top of the bar counter or the kegerator to hold the faucet (the point of dispense) in place. Inside the tower are the beer lines and in some cases the glycol cooling lines. Towers can be either air-cooled or glycol-cooled to maintain ideal beer temperature and come in a variety of shapes and sizes. They can hold as few or as many faucets as desired, and may be made from a variety of materials including brass and stainless steel.

Trub (pronounced "trub" or "troob")

The layer of sediment at the bottom of the fermenter after fermentation that consists of hot and cold break material, hop bits, and dead yeast.

Water Conditioners

A component of a blended cleaner that is intended to carry away soils.

Water Hardness

The degree of dissolved minerals in water.

Water Stone (Calcium Carbonate)

A mineral deposit that forms from water and can be removed with acid.

Wort (pronounced "wart" or "wert")

The malt-sugar solution that is boiled prior to fermentation. The wort before boiling is called "sweet wort"; after boiling (with hops) it is called "bitter wort". Wort is high in sugar and ferments when yeast is added, becoming beer.

Zymurgy

The science of brewing and fermentation.