Beer Brewing Glossary: A Complete Brewer’s Index

March 19, 2022 // 61 minute read

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Whether you’ve been a long-time brewer now or just starting out, it never hurts to learn some more beer terminology; doing so will help you improve your craft even more or avoid any confusion.

Read on to see our compiled list of essential beer-related terms that every brewer needs to learn.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z



Any ingredient outside of the four essential ingredients that brewers add in brewing. Adjuncts’ purpose is to increase the sugar level or add certain flavors and aroma to the beer. Adjuncts could be anything from unmalted grains to fruits and various types of sugars and syrups.


The process of adding oxygen to the wort via air. It takes place before fermentation and after the boil. This is to ensure that the wort will have enough oxygen for yeast growth and reproduction. It also helps to achieve a complete fermentation cycle.

airlock (or fermentation lock)

A device attached to the top of the fermentation vessel. It lets out the carbon dioxide created during fermentation from the fermentation vessel. It also prevents oxidation by blocking air from getting inside the fermentation vessel.


A beer type that features a full body and a sweet, fruity flavor with a note of bitterness. It has a strong hop aroma and a robust quality, as well. Ale is a warm-fermented beer. Thus, it is best served at warmer temperatures, generally speaking. Also a term for top-fermenting beers.

alpha acid

A chemical compound inside the resin glands, together with beta acids. The flower of the Humulus lupulus or hop plant houses the resin glands. During the wort boiling process, alpha acids get converted into iso-alpha acids. They then become the main source of the bitterness in the beer.

alpha acid unit (AAU)

Also known as Homebrew Bittering Unit (HBU). Alpha Acid refers to the measurement method to gauge the hops’ bittering potential. To calculate it, take the hops’ alpha acids percentage and multiply it with the hops’ weight in ounces.


The enzymes that break down complex starch molecules into more soluble, smaller ones. They are also responsible for producing fermentable sugars.


During fermentation, glucose gets converted into alcohol and carbon dioxide gas. The conversion that takes place is Attenuation.



Single-celled microorganisms. They are everywhere on the earth, from rock and soil to water, food, and human bodies. Bacteria like lactic acid and acetic acid can cause contaminations in beer. These contaminations result in off-flavors in beer.

Balling Degrees

Balling Degrees is a measurement system to measure the sugar density in the wort. Karl Balling developed the system in 1843.


Barley, or Hordeum vulgare, is a cereal plant that is part of the Poaceae grass family. It is a source of malt and is one of the main ingredients for brewing beer, wine, and many alcoholic beverages.


A popular alcoholic beverage made from water, malted grains, hops, and yeast. It’s produced through brewing yeast and fermentation.


Having a strong, sharp, and pungent taste that is the opposite of sweet.


In beer brewing, the hops release alpha and beta acids. Then they get converted into Iso-alpha acids during the boiling step. Those acids then cause bitterness in beer. Depending on the style of beer, the level of bitterness will vary from beer to beer.

Black malt

Also known for its former name “black patent malt,” black malt is the darkest variety of roasted malts. It provides a dark color and a roasted flavor to beer. That makes it ideal for brewing darker types of beer, such as Porters and Stouts.


The general word used for the beer’s richness, density, and how the beer feels in the mouth. Light, medium, and full are descriptors for the beer’s body.


A method where beer is carbonated through priming with sugar or yeast. This process takes place before packaging the finished beer.

Bottom-fermenting yeast 

The yeast for brewing bottom-fermented, Lager beer types. In 1870, it was given the official taxonomical classification of “Saccharomyces pastorianus” by Max Reess.


A brewhouse or a brewery is a building where the beer-making process takes place.

Brew Kettle

The brew kettle is a piece of essential equipment for beer brewing. It’s used as a vessel for boiling sweet wort with the hops and is usually made of stainless steel or aluminum. Also known as the boil kettle.


Any pub or commercial establishment that makes and sells beer.

Bright Beer Tank (BBT)

A piece of brewing equipment for clarifying and carbonating the beer. Those processes take place after the fermentation and before bottling or kegging. Most brewpubs also used these tanks to serve beer.


A conical-shaped stopper that is usually made of plastic, rubber, or wood. Brewers prevent oxygen from entering the fermenter by placing it in the hole to seal the carboy.


A beer off-flavor produced by a compound called Diacetyl (2 3-butanedione). Bacterial contamination— in particular Lactic acid, Pediococcus, and Lactobacillus— is the common cause.



A word used to describe an off-flavor and aroma in the beer that is similar to the vegetable cabbage. This is usually caused by using spoiled hops or malt in brewing.


A cylindrical-shaped device used as an extra heat source for boiling the wort. It is either positioned vertically inside the boil kettle or on the outside of the kettle.

Calcium Carbonate (CaCO3)

Also known as food-grade chalk. Brewers use this mineral during the beer brewing process to raise the beer’s pH levels. It also increases the carbonate and calcium content in the beer. When used sparingly, it is also effective at reducing the acid amount in the beer. It is generally used for brewing darker styles of beer.

Calcium oxalate

A crystalline deposit that’s yellowish-brown in color. It is created when calcium reacts to the oxalic acid that’s released during the mashing process. It can be found in beer kegs, bottles, and tanks, and can be extremely hard to remove. Calcium oxalate is also commonly referred to as “beer stone.”

Calcium Sulfate (CaSO4)

A mineral used for increasing hardness to the mash via calcium ions and for enhancing the hops’ sharpness as well. Also known as Gypsum.


An acronym that stands for Campaign For Real Ale. It was founded in 1971 by Bill Mellor, Jim Makin, Graham Lees, and Michael Hardman. The English independent organization aims to promote the production and availability of what it deems as “real ales.” It is also a founding member of the European Beer Consumers Union or EBCU.


A thick, dark brown liquid that’s made from heated sugar. It is commonly added to the wort to give the resulting beer a stronger flavor and enhance its color.


The most common type of organic compound that includes starches and sugar. Most of the beer’s carbohydrates come from starch-rich grains in its ingredients.

Carbon Dioxide (CO2)

The colorless gas that results from the carbonation of the beer and is responsible for giving the beer its bubbles and fizz.


The process of adding carbon dioxide to the beer in order to give it fizz and bubbles, which will result in a foamy head. It can be done by either natural carbonation or forced carbonation.


A large container that is usually made from glass or plastic. It is used to hold corrosive liquids. Typically, a carboy has a 4-60 liters capacity. Also called a demijohn.


An extract that’s been sourced from seaweeds. It is used in beer brewing to aid in removing all the excess protein from unfermented beer that could possibly cause a beer haze.


An essential oil that gives hops an earthy, spicy-sweet flavor.


A barrel-shaped container that has a curved, bulging middle and flat ends. It is designed to hold foods or liquids. Casks are traditionally made from wood, but modern-day casks can be constructed from aluminum or stainless steel.

Cask breather 

A demand valve that is usually used together with a pressure regulator to dispense cask-conditioned or draft beer. It is often called a cask aspirator as well.

Cask conditioned beer

Unpasteurized and unfiltered draft beer. It also went through a secondary fermentation and a clarification process in a cellar. It is served from a cask at a cool temperature.

Cask Conditioning

The method of storing unpasteurized and unfiltered beer in a cool cellar. For several days, the beer is stored at a temperature between 48-56 degrees Fahrenheit (13 degrees Celsius). This process allows for natural carbonation to occur.


The process of aging beer in a cellar within a certain time frame, depending on the style of beer.

Cereal cooker

A vessel that is used in brewhouses to incubate the malt before the mashing.

Chill Haze

A form of beer haze or turbidity. It occurs when the beer is cooled at very low temperatures, around 32 degrees Fahrenheit (0 degrees Celsius). It can disappear at a warmer temperature of 68degreese Fahrenheit (20 degrees Celsius). It also appears as a result of an improper cold break or failing to chill the wort quick enough during the cold break. It can develop into a permanent haze.


A term that is used to describe the chemical reaction of chlorine with phenol compounds. It produces a plastic-like flavor and aroma.


One of the primary components of alpha acids. It gets extracted from the hops when boiling the wort and transforms into iso-cohumulone, contributing to the beer’s bitter flavor.

Cold Break

The precipitation of proteins, tannins, and hop debris that occurs when the wort is quickly chilled.


Refers to the beer’s shade or hue that is mostly determined by its ingredients. Specific styles of beer that are made with roasted, toasted, or caramelized malts will exhibit darker colors. On the other hand, beer styles with a light grainy flavor will appear lighter most of the time. The Standard Reference Method or SRM is used to assess the color of the beer or wort.


A beer brewing step that involves aging and carbonating the beer to diminish unwanted flavors and let new ones emerge during the process. It also helps prevent beer from ending up flat.

Contract Brewing Company

A brewing company that hires another brewhouse to produce either some or all its beer.


A protein that can be found in isinglass finings, a material that is used for clarifying beers.

Conditioning Tank

A tank used as a vessel for the conditioning of the beer after the fermentation process. It is synonymous with serving tank, secondary tank, and bright beer tank (BBT).


Another name for brew kettle.

Copper whirlpool

A vessel used for separating the hop pellets and trub from the wort after the boiling process.

Craft Brewery

Generally refers to a small brewery that manufactures beer using traditional methods. Craft breweries are very often independently owned. Another characteristic of a craft brewery is its emphasis on quality and innovation.


Decoction Mash

A traditional method of mashing that involves removing a portion of the mash from the mash tun. The mash is then boiled and returned to the main mash in the tun, with the aim to raise the temperature of the mash for the next step. This method is mainly used in all-grain brewing.

Degrees Plato

A scale used in fermentation to measure the wort’s specific gravity during different stages of fermentation. It was developed by the German chemist Fritz Plato in the early 1900s.


A group of unfermentable and complex carbohydrates that are formed during malting and mashing from the barley’s enzymes. While they are tasteless, the remaining undissolved dextrins in the beer can result in a certain malty sweetness. They also contribute to the gravity, body, flavor, and mouthfeel of the final beer.


An organic compound that is produced by some yeasts. It results in a distinctive buttery or butterscotch aroma and flavor in the beer. Low levels of Diacetyl are acceptable in some styles of beer, such as Czech Pilsners, Scottish Ales, and English Ales. It is a natural by-product of fermentation but can be considered an undesirable off-flavor in certain beer styles.


Refers to the enzymes that are created as grain sprouts. These enzymes then work to break down and convert the starches into fermentable sugars and dextrins.

Dimethyl Sulfide (DMS)

A very volatile, organic sulfur compound. It can impart a flavor and aroma like cooked vegetables such as cabbage, creamed corn, brussel sprout, celery, or black olive to beer. It is considered acceptable at low levels in some Lager beers but an unwanted off-flavor at high concentrations. It is commonly caused by slow wort chilling and bacterial contamination.

Dissolved oxygen (DO)  

Basically just the amount of oxygen that has been dissolved in the wort. Too little dissolved oxygen can result in poor fermentation and off flavors. Meanwhile, too much can cause the finished beer to become stale or have an unwanted fruity flavor.


The practice of adding yeast and sugar to the vessel to help with the secondary fermentation.

Dough Ball

Balls of crushed grain that form in the wort during mashing.

Draft Beer

Beer that is drawn and served from kegs, serving tanks, or casks instead of from bottles or cans. Also called draught beer.

Draught Beer 

See Draft Beer.

Dried Malt Extract (DME)

Malt extract that has undergone a dehydration process to remove its water content, resulting in a dried form. Because of its dry nature, it has a longer shelf life than the Liquid Malt Extract of LME.

Dry Hopping

The process of adding uncooked dry hops in the late stage of the brewing process (usually after the boil) to boost the final beer’s hop flavor and aroma without increasing the bitterness.

Dry kit

A kit for beer homebrewing that includes dry malt extracts together with hops and specialty malts.

Dual Purpose Hops

These are hops that are used for both their bittering and aromatic characteristics.

Dwarf hops  

Hops that are low-growing and don’t grow taller than 3 meters. Boadicea, First Gold, Pioneer, Sovereign, Pilot, Sussex, and Endeavor are some of the most common dwarf hop varieties.



Stands for European Brewing Convention.  Founded in 1947 and based in Brussels, EBC represents Europe’s brewing sector.


The fizzing and foaming in beer, wine, soda, and other beverages, which is a result of the carbon dioxide gas being released.

Emmer wheat

A type of awned wheat that is also known as Triticum dicoccoides. It has been used in baking and brewing beer since ancient times, particularly in ancient Egypt. Its hull is capable of assisting in wort clarification after the mashing, which makes it ideal for brewing.


The portion of the cereal grains where the starch is stored.


Special proteins that are found in the grain. They are made up of many different and unique amino acids— the uniqueness of each one’s structure is what allows them to do a particular task. They work by catalyzing and speeding up chemical reactions while remaining unchanged. Beta-glucanase, Alpha-amylase, Beta-amylase, and Protease are the four enzymes used in brewing.

Essential Hop Oils

Hop oils that are extracted from hop flowers or cones of hop plants. The aromatic and flavor compounds that are associated with various hop additions are provided by essential hop oils.


Strong and volatile organic flavor compounds. They are formed during fermentation when organic acids interact with alcohols. Esters contribute flowery, fruity, or spicy flavor to the beer.


A floral or fruity aroma or flavor in the beer, which can be caused by certain yeast strains.


Also known as ethyl alcohol or grain alcohol. Ethanol is a colorless liquid that is used as the primary alcohol component of beer and other distilled beverages.

Ethyl acetate

The most common ester found in beers and wines. It is produced by brewing yeast during the fermentation stage when the ethanol and acetate get combined. At low concentrations, it will present as a fruity flavor, specifically, a pear-like taste. Yet, it can turn into an unpleasant solvent-like off-flavor and aroma at higher concentrations.


A beer produced specifically for the purpose of exportation. These beers are modified to suit the taste of a foreign market. Export-style Irish Stouts and Guinness Special Export are some examples of Export beers.


Fahrenheit (degrees)

A temperature scale. Based on this scale, 32 degrees Fahrenheit is the melting point of water, while the boiling point is 212 degrees Fahrenheit. It was named after the German physicist Daniel Gabriel Fahrenheit, who developed it in the early 1700s. He also designed the first precise and accurate mercury and alcohol thermometers.


One of the four primary essential oils that are found in Humulus lupulus or hop plant. The other three are humulene, caryophyllene, and myrcene.

Fermentable Sugars

These are the sugars that are consumed by yeast during fermentation and converted into ethyl alcohol and carbon dioxide gas. Fermentable sugars are glucose, fructose, maltose, maltotriose, and sucrose.


A metabolic process in which fermentable sugars get converted into carbon dioxide gas and ethanol (C2H5OH). This process is a change that is brought by the yeast’s action. In beer brewing, there are two methods of fermentation, top fermentation and bottom fermentation.


A barrel, tank, or any container that is used as a vessel for fermenting wort. Fermenters come in a variety of shapes and sizes and are commonly made of stainless steel. They are also known as fermentation vessels.

Ferulic acid

A phenolic compound that is found in the endosperms’ cell walls of starchy cereals such as barley, wheat, and oat. During fermentation, it results in the formation of 4-vinyl guaiacol. In turn, this causes a distinctive clove-like aroma, which can be considered as an off-flavor, depending on the style of beer being brewed.


The process that is done at the completion of the brewing process and before bottling. The beer passes through a filter to remove solid matter and impurities from the beer for clarification.

Final specific gravity

Refers to the specific gravity of the beer, measured with a hydrometer, after the fermentation process is completed. Also called terminal gravity or finishing gravity.


The process of adding finings or clarifying substances to the wort. This is done near the end of the brewing process to aid in removing organic compounds, resulting in beer clarity. Some examples of finings used for this process are Isinglass, Irish Moss, gelatin, Biofine® Clear, and Super-Kleer KC Finings.

First runnings 

The initial wort that is collected from the brew kettle. It is then transferred into the fermentation vessel after the mashing process and before sparging.


The phenomenon when yeast cells clump together in a large mass during fermentation. Depending on the yeast strain that was used, the mass will either float or sink to the bottom of the vessel. That is because various yeast strains have different flocculation abilities.


Also called the beer head. It is the froth on top of the beer that is formed when the gas bubbles, mostly carbon dioxide gas, rise to the surface. Those gas bubbles are produced during fermentation. The type of malt and adjuncts that are used to ferment the beer will impact the longevity and density of the foam.

Forced Carbonation

One of the two methods for carbonating the beer. With this method, the beer is transferred to another vessel, sealed tight, and the CO2 is forced into the beer from a gas cylinder.

Fresh Hopping 

The term for adding freshly harvested and undried hops at various stages of the beer brewing process. This step imparts unique aromas and flavors to the beer. Those are different from the ones that result from using processed hops that have been dried.


A type of sugar and naturally occurring sweetener found in fruits, honey, and certain vegetables. It is one of the three monosaccharides or “single sugar,” along with glucose and galactose.


See Estery.


A variety of hops. Fuggle hops are recognized as the classic English aroma hop and an important ingredient in traditional English beers. It can be used for dry hopping, as well. Named after Richard Fuggle, who introduced it in 1875 after being discovered in 1861.

Fusel Alcohol 

Alcohols that are by-products of fermentation at extremely high temperatures. Fusel alcohols can result in off-flavors in beer that can be described as solvent-like or tasting like acetone or paint thinner.



A colorless fining agent that is used to clarify beer. It is also effective in reducing bitter after-taste in beer.


The process wherein the starch is dissolved in hot water, resulting in the starch transforming from solid to a thickened gel-like form.


The process in which the barley grains grow while producing a rootlet and acrospire.


Glucose polymers are present in barley and malt, specifically in the endosperm’s cell walls. They are released during malting and mashing into the wort. It is also a term that is used to refer to beta-linked glucose polymers.


An enzyme that is found in cereal grains. It catalyzes hydrolysis, which breaks down large polysaccharides. It results in the production of glucans.


A carbohydrate reserve that is formed before yeast runs out of nutrients and sugars, for emergency purposes. Glycogen allows yeast to survive long periods of inactivity while also assisting it in starting a new fermentation.

Glycol Chiller

A specialized cooling device that is primarily used in beverage productions. It is used for cooling various liquids and beverages. Basically a refrigerator that uses food-grade propylene glycol to lower or maintain temperatures. The temperature will depend on what a certain brewing process requires.

Grain Auger

An agricultural device that is used for moving uncracked grains to be grounded in the grain mill. It is also used to transfer cracked grain to the grist case and to the brewery for the brewing process.

Grain Mill

An equipment that is used in grinding and milling the grains, malt, and adjuncts that are going to be used for brewing. This step is crucial for removing unwanted internal components.


Having a taste or aroma like that of raw or wet grains or cereal.

Gram-negative bacteria

Bacteria that, using the Gram Staining method of bacterial differentiation, stain red due to a thin peptidoglycan wall. They also don’t retain the crystal violet present during the decoloring procedure.

Gram-positive bacteria

Bacteria that stain violet after undergoing the Gram Staining method of bacterial differentiation. That is a result of the presence of a thicker layer of peptidoglycan in their cell walls. They retain the crystal violet during the decoloring procedure.


In beer brewing, gravity refers to the measurement of the wort’s density at various stages of the fermentation process. Knowing the gravity is important as it affects the alcohol levels in the beer.


The malt and cereal grains that have been milled or grounded in a malt mill before the beer brewing process, to be used in mashing.

Grist Case

A storage vessel that is used to store cracked grain. A grist case is placed between the grain mill and the brewhouse and is the intermediary stop for the grain before being used in brewing.

Grist Hydrator

A brew kettle/mash tun accessory used to wet the crushed grain while the grain auger is pouring it into the mash tun. The use of a grist hydrator helps in preventing dough balls from being formed.


A container with a jug-like appearance and is commonly made from dark glass (but can also be stainless steel or ceramic). They are commonly seen at craft breweries, where they are used for beer refills and to transport draft beer. While growlers come in various sizes, they typically have a 2-liter beer capacity.


A mixture of herbs, namely Common heather, Yarrow, Mugwort, Ground Ivy, Sweet gale, and Horehound. It was used before the widespread usage of hops for bittering and flavoring beer. Alternative names: Grut, gruyt.


A term that describes the sudden, explosive release of carbon dioxide gas, beer, and foam after opening the bottle. Also known as fobbing. Anything that encourages the quick release of gas in beer will result in gushing. Using defective malts or a bottle with a rough internal surface and the presence of metal ions (nickel, iron, and tin) are some of its common causes.


A form of calcium sulfate (CaSO4) that is usually used to harden the brewing water or added to the mash to lower the pH. Its sulfate content can also enhance the bitterness of the beer.



A type of aroma hops that is popular for brewing German-style beers.

Hand Pump

Also known as a Beer Engine. A device used for dispensing cask-conditioned draft beer.


The term that describes any bitterness that lingers after drinking beer.

Hard Cider

An alcoholic beverage that is produced by fermenting fruit juices, mainly apple juice. The “hard” in its name indicates that it is an alcoholic beverage. Therefore, it shouldn’t be confused with apple cider, its non-alcoholic counterpart.


Refers to the hardness of the water that is used for brewing. It is determined by the level of calcium and magnesium concentration in the water. Water hardness can greatly affect the finished beer. High levels of calcium and magnesium are great when aiming to emphasize the beer’s hoppy flavors. They also create a darker beer profile and a rich mouthfeel.


A term for the turbidity in beer that occurs because of suspended yeast or the presence of proteins and polyphenols. Beer haze is harmless, or even desirable, in some types of beer such as New England-style IPA, Hefeweizen, and American wheat ales. However, it is considered a flaw most of the time as it can also indicate other problems like bacterial contamination.


A term that is synonymous with foam.

Head Retention

The term used for describing the longevity and stability of the foam or beer head in a glass of beer.

Heat Exchanger

A piece of brewing equipment that is used for rapidly increasing or lowering the wort’s temperature.


In Scottish ale terminology, it refers to beers that have a 3.5-4.0 percent ABV, which are considered of medium strength. They are also characteristically dark and malty and don’t have a prominent hoppiness.


A German term for the word “yeast.” In Germany, it is usually used to differentiate filtered and unfiltered beers. Unfiltered wheat beer is called “Hefe-Weizen”,  while filtered wheat beer is labeled “Weissbier”.

High gravity

Refers to beers that were brewed with a wort that has a high density relative to water. High-gravity brewing provides more sugars for the yeast to break down during the fermentation process. It results in a beer with a high ABV. Hence, high gravity can also refer to beers with strong alcohol content.


An old English word for large casks that are used for transporting beer for shipping or to pubs. They have a minimum of 54 Imperial gallons (65 US gallons) capacity. Hogsheads have a barrel shape and were commonly used in 18th- and 19th-century Britain.


The process of brewing beer, wine, ciders, or mead on a small-scale that is not for commercial purposes. For beer brewing, the main ingredients are water, cereal grains (which can be malted barley, rice, wheat, maize, etc.), hops, and yeast. A brew kettle, a long stirrer, a fermentation vessel, an airlock, a siphon, and bottles or kegs are the basic equipment for homebrewing. Sanitization, Mash, Boiling, Cool down, Yeast pitching, and Fermentation are the main steps of homebrewing.

Home Bittering Unit (HBU) 

A method that is created to determine how many hops are needed to achieve a given bitterness in beer. This was introduced by Charles Papazian in his book “The Complete Joy of Homebrewing.” Also known as Alpha Acid Unit.

Hop back

A device that is designed to retain the hops while the hot wort exits the brew kettle and passes through the hop back before the chilling process. It is also called hop jack in the US.

Hopback Grant 

A vessel that is positioned between the brewing kettle and the wort chiller. It serves the combined functions of a hopback and a wort grant. Known as hop jack in the US.

Hop oils 

A component of the hop plant. Although they only make up about 4 percent of hops, hop oils are a very important component as they give the beer its flavor and aroma. Hop oils consist of many components, the four most prominent ones being: Myrcene (53%), Humulene (22%), Caryophyllene (8%), and Farnesene (6%).

Hop resins

The chemical compounds that are created as secondary metabolites by the Humulus lupulus or hop plant. They are necessary for the plant’s development and survival even without being involved in the metabolic process.


The green, cone-shaped flowers of the Humulus lupulus plant used to flavor beer. Inside the hops are found the lupulin, which are small yellow glands that are responsible for imparting bitterness to the beer.


A word that means one can taste and smell the hop characteristic in the beer, be it bitter, fruity, or floral, depending on the type of hops that were used.

Hot Liquor Tank (HLT) 

A device that is commonly used by all-grain brewers for heating brewing water to mash temperature and sparging water. Contrary to its name, it doesn’t hold wort or alcoholic beverages.

Hot Water Extract (HWE) 

Refers to the measure of the total amount of dissolved solids that have been extracted from the malt or other ingredients into a solution. It is assessed in a brewhouse or using a laboratory scale.

Human Machine Interface (HMI)

A user interface or dashboard that is used for a person to be able to connect to a system, device, or machine. In the context of beer brewing, HMI is useful for brewers as it allows them to monitor and regulate temperatures precisely. It also lets them remember the exact times and temperatures of each brewing step for repeated brewing. This makes it easy for brewers to save and exchange recipes with fellow brewers.


One of the four essential oils that are found within the hop plant (Humulus lupulus).


The external protective layer of cereal grains.


An instrument made of glass that utilizes the concept of buoyancy to measure liquids’ relative density. In beer brewing, a hydrometer is an important tool to determine the ABV (Alcohol by Volume) of the beer. It is done by measuring its Original Gravity and Final Gravity.



An acronym that stands for International Bitterness Units. A scale that measures the bitterness that is provided by hops to a beer during beer production. Most beers will have an IBU range between 15-80, but a beer can have an IBU score as low as 5 or as high as 120.

Ice beer

A beer style where the beer goes through a process called fractional freezing or freeze distillation until ice crystals form. The extremely cold temperature creates a chill haze and precipitation. Those are then filtered out, leaving a clear, clean-tasting-beer. The beer also has a stronger flavor compared to regularly brewed beer. This was first popularized in the 1990s, particularly in Japan, the UK, the US, and Canada, where it is also known as “pale lager.”

Immersion Chiller

A tool that is usually made of copper or stainless steel coil tubing. It is inserted into hot wort as part of the wort chilling process before fermentation. It works by providing the cooling liquid to the hot wort via the coil, all the while taking away the heat until the wort cools down completely.

Immobilized yeast 

Yeast whose mobility has been severely or completely restricted during fermentation. This results in a clearer beer and, possibly, a higher ABV in the finished beer.

Infusion Mash

A traditional British mashing technique that is mainly used for brewing ales. This method involves creating a mash using a mix of hot brewing water and malts, with only one rest, at mashing temperature. An infusion mash tun is usually used for this step. It is also known by the terms “single-infusion mash” or “British infusion mash.”


Refers to the introduction of microorganisms, such as yeast, into the wort at the start of the fermentation.

Insulation Jacket

A removable jacket made from insulating materials that is used for controlling the temperature of brew kettles or tanks.

Invert sugar 

A brewing adjunct that is produced when sucrose is broken down into glucose and fructose by acids or enzymes. It is popular for brewing Belgian- and English-style beers, as well as for high-gravity brewing as this sugar is more easily fermented by yeast.

Irish Moss

A fining agent that is derived from the red seaweed Chondrus crispus. It is added to the wort at the end of the boil to help encourage protein precipitation. This helps avoid any chill haze from occurring, ensuring beer clarity.


A mineral that naturally occurs in brewing as an ion. High concentrations of iron can affect the beer’s color and taste, so it is usually kept at no more than 1 mg per liter concentrations.


A gelatinous substance extracted from a sturgeon fish’s swimming bladder. It is used as a clarifying and stabilizing agent to a fermented beer.


Jetting machine

An equipment that is used for cleaning bottles.


A type of beverage made with ale that has been sweetened with apples and nutmeg.

Jockey box

A portable draft system that is used to dispense beer. It is made up of an insulated cooler with internal coils that are connected to the external draft beer faucet. Ice is placed inside the cooler, and the beer flows from a keg to the jockey box through a beer line that is connected to the shank at the back of the jockey box. The beer then runs through the internal coils into the external beer faucet. It is used for keeping the beer fresh and cold and to reduce foaming. Jockey box got its name from the phrase “jockey around,” which means “easy to move from place to place.” It is sometimes called the coil box.



A cylindrical container the size of a small barrel. It is used to hold, serve, and transport beer. Traditional kegs are wooden, but modern ones are commonly made from aluminum or stainless steel. Kegs come in a variety of sizes: 2.5 gallons, 5 gallons, 7.75 gallons, 13.2 gallons, and 15.5 gallons.

Keg Washer  

A machine for cleaning kegs. It works by rinsing, washing, sterilizing, and pressurizing kegs. These machines come in manual, semi-automatic, and fully automatic varieties. A lot of keg washers can handle cleaning multiple kegs at the same time.


Brew kettle keg. A term that is used for a beer keg that has been through a keg-to-brew kettle conversion.


An essential piece of equipment for homebrewing. It is used to heat and boil the wort.


The method of producing dry malt that is easy to mill, by heat-drying malted barley in a kiln and stopping germination. This process aids in developing new flavors and aromas. It also removes the raw flavor that is associated with germinating barley.


The rocky, foamy head that forms on the surface of the wort during the fermentation stage. Homebrewers use it as an indicator of whether the fermentation is ongoing or is finished. When the Krausen crashes, that means the fermentation has been completed.


The process of adding a small portion of unfermented wort to a brewed beer during the lagering stage. This stimulates secondary fermentation and creates natural carbonation.



The name for the pattern of foam with a lace-like appearance. It can be seen sticking to the sides of the glass that has been partially or completely emptied of beer.

Lactic acid (2-hydroxypropanoic acid)

A chemical compound that is produced by bacteria and yeast during the fermentation stage. It creates a prominent sour flavor, which is considered acceptable in certain beer styles. On the other hand, it can also cause the formation of Diacetyl and other off-flavors. Known also as milk acid.


A microorganism that metabolizes unfermented sugars into lactic acid. It results in a sour off-flavor in the beer, which is considered a flaw in most beer styles. Lactobacillus is widely used in fermenting other food products such as yogurt and sourdough bread.


Any bottom-fermented beer that has been brewed and then conditioned and served at cold temperatures. Lagers are also characterized by a clean, crisp, and light beer flavor and more carbonation when compared to ales. They come in a variety of colors, which can be pale, dark, or amber.

Lager Yeast  

Saccharomyces pastorianus. A bottom-fermenting type of yeast that is used for producing lager-style beers. This yeast ferments at very cool temperatures, ranging between 45-55 degrees Fahrenheit. Some lager yeast strains can also ferment at a temperature as low as 32 degrees Fahrenheit. Usually, lager yeast ferments more sugar when compared to ale yeast. This results in the characteristic smoothness and crispness of lager beers. It was named after the French chemist Louis Pasteur.


Refers to storing bottom-fermented beers in a cold cellar for a certain time period, which can range from several weeks to years. This process uses a temperature of 32 degrees Fahrenheit or 0 degrees Celsius. The purpose of this is to let the residual yeast settle, which results in a clearer beer. With this method, the beer also develops carbonation, and its flavors get enhanced.


A Belgian style of wheat beer brewed from unmalted wheat and malted barley, traditionally in the winter. This style is unique from other beers in that it is produced using a spontaneous fermentation style. That means that it is fermented through airborne bacteria and wild yeast. The types of lambic beers are Kriek lambic, Framboise, and Gueuze.

Large Brewery

A type of brewery that manufactures over six million barrels of beer annually. Large breweries are also called macro breweries.


The process of separating the pre-boil sweet wort that is created during mashing from the spent grains using a lauter tun. The three steps of lautering are mash-out, recirculation, and sparging.

Lauter Tun

A large vessel that is used for the lautering process. It is constructed with a false bottom, which is a slotted, perforated floor, that holds the spent grains, and a filtering bed that filters the wort. The filtered wort then flows into the brew kettle.


Refers to the total amount of wort that has been brewed in a brewery each time it is in operation.


A flavor and aroma defect, resulting in a skunk-like smell in beer. It is produced when the beer gets exposed to heat and light, caused by light-colored bottles. A beer that is affected by this is called “skunked beer.”


A group of diverse chemical compounds including fatty acids such as terpenoid lipids and glycerides. Lipids make up about 2.2-2.5% of the barley’s dry substance while making up 2-12% of the yeast cells’ dry matter. While lipids are important for yeast reproduction, the presence of lipids in the final beer is a negative thing. It can affect the beer’s foam and aging stability.


A term that’s used in the brewing industry to refer to the water used for beer brewing, specifically in the mashing and sparging processes.


The scale that is used for measuring the grains’ color and level of darkness (a high number signifies a darker malt). It was named after J.W. Lovibond, who created the original system.

Low alcohol beer

Any beer that has been produced using wort with low gravity, leading to low alcohol content. Also commonly called low-gravity beer or “session beer.”


One of the four beta acids found in the hop resin, along with Colupulone, Adlupulone, and Prelupulone.


Magnum Bottle 

A bottle with a 1.5-liter capacity, which is the size of two 750ml standard liquor bottles.

Maillard Reaction

The non-enzymic browning that contributes color and flavor to the beer. It was named after Louis-Camille Maillard, the French chemist who discovered it in 1910.


The process wherein the dry grain is steeped in water to stimulate germination. It is then kilned and converted into malt, one of the main ingredients in brewing. Malting is the first brewing step, followed by mashing, boiling, fermentation, and bottling.

Malt Extract

The sugar that is produced during a mashing process and dehydrated into a syrup or dry powder. It is then used in brewing, particularly by beginner homebrewers, to create wort.

Malt Liquor

A term used chiefly in North America to refer to a beer that has a high alcohol content (no lower than 6%). They are produced using ingredients and processes like those used for brewing American-style lagers.


A disaccharide that is the main fermentable sugar in the wort. It is created when the starch gets broken down during the mashing process.


A trisaccharide that is produced during the mashing after the breakdown of starches by enzymes.


Refers to the resulting mixture of hot water, malt grains, and sometimes adjuncts, after they’ve been steeped together.

Mash filter

A device that is used for separating the sweet wort from the mash after the mashing. It is common in large-scale brewing. It is also used as a substitute for a mash or lauter tun.

Mash Tun 

A vessel that is used in soaking the grist (ground malt and cereal) in heated water in order to convert starches into sugars. Another purpose of that process is to extract the sugars and solubles from the grist.


An acronym that means Master Brewers Association of the Americas. It is a US-based food and beverages company that was established in 1887. It is also the publisher of the technical journal, the Technical Quarterly.


An alcoholic beverage that is produced with water, fermented honey, and sometimes mixed with additional ingredients like herbs, fruits, and spices. Meads’ alcohol percentage usually ranges between 3.5-18+% ABV.


The brown-colored compounds that are created during the Maillard reaction during malting. These compounds contribute a malty flavor to the beer and can also generate flavors like caramel, honey, and biscuit. They help in protecting the wort from oxidation as well.


A beverage that is made by flavoring mead with fruits.


An off-flavor in beer that presents as a coin-like, blood-like, or tinny taste. It is commonly caused by high concentrations of iron in beer or by using metallic equipment during the brewing process.


Highly toxic alcohol. Methanol can be found in some beers as it is an unintended byproduct of fermentation. Those are only very small amounts and won’t have any harmful health effects. 10ml of methanol can cause permanent blindness, 15ml can be fatal, and 100ml is considered a completely lethal amount. Synonymous to methyl alcohol. 


A type of mead that is flavored with spices.


The term used for a small brewery that has an annual production of fewer than fifteen thousand barrels of beer in total. The majority of the microbrewery sales are also made outside of its premises.

Mild ale 

A type of beer that is characteristically low-gravity, dark, malty, lightly hopped, and has a low strength (3-3.6% ABV). It originated from Britain in the 1700s.


The process of grinding the malt, grains, or adjuncts into grist to be used for mashing and lautering, which are the next steps of beer brewing. This results in smaller particles. Those particles make it easy for the sugars and other soluble substances to be extracted from the grist during mashing. The grains’ husks are kept intact to serve as a filter aid during the lautering stage.


The physical and chemical changes in the grains after undergoing the process of malting and being converted to malt. In particular, it refers to the breakdown of the compounds that are found inside the grains.


The textural characteristics of beer, including the beer taste, bitterness, carbonation, fullness, and aftertaste.


A flavor defect that gives the beer a moldy and mildewy flavor and/or aroma. It is usually a result of bacterial contaminations in beer and commonly occurs during fermentation.


One of the four primary essential oils that are found in Humulus lupulus or hop plant. The others are farnesene, humulene, and caryophyllene. It provides a fresh and herby aroma to beer.


Natural Carbonation  

The method of transferring the beer to a keg to carbonate it. Priming sugar is then added to it, and the keg is sealed. The yeast will then consume the sugar and it will result in the production of CO2. The trapped CO2 will turn into carbonic acid, which will produce the fizz in the beer.


The goddess of beer in ancient Sumerian mythology.


A chemical element that, in its gaseous form, is often used as a substitute for CO2 when carbonating the beer. In comparison to CO2, Nitrogen produces smaller bubbles. This results in a headier and smoother beer with a creamier mouthfeel. It is also used by brewers for purging the vessels that were used for the brewing of any wort or beer, preventing off-flavors from developing. 


The process of adding nitrogen gas to the beer, which results in a smoother, creamier mouthfeel and thicker, longer-lasting foam. This method is mostly associated with Irish stout beers. However, many other styles of beer also use nitrogenation, producing what is called nitro beer.


Organic compounds that are considered carcinogenic. They can form during the beer production process as an unintended by-product when nitrates merge with amines. Nitrosamines are formally known as N-Nitrosamines.

Noble Hops   

A group of hop varieties is used mainly in brewing European-style beers, particularly Pilsners and European lagers. The flavors and aroma that noble hops provide to beers are delicately spicy, floral, herbaceous, and more subdued. The four varieties of noble hops are Spalt, Hallertau Mittelfrüh, Saaz, and Tettnanger.


Refers to the aroma that a beer, wine, or coffee gives upon tasting it.


A hops variety from North America that has a distinctive bitter and woody flavor and aroma. Because it possesses a high alpha acidity and low beta acid level, it is mostly used as a bittering hop or a balancing aroma hop.


The nutrients needed by the yeast for a healthy yeast reproduction before and during the fermentation stage. Examples of nutrients that the yeast need are various vitamins, amino acids, fatty acids, phosphorus, and nitrogen.


Oast house

An agricultural building that is designed to be used for drying, aging, and kilning the hops after picking and before the brewing process.

Oats (Avena Sativa)

A cereal grain that is popularly used in beer brewing, as malted oats impart a rich, smooth, and velvety texture to a beer. Can also be referred to as common oat.


A term that can be used to refer to either the beer festival or a type of beer. The Oktoberfest festival is an annual event that is held in Munich, Germany, with around six million people attending from all over the world. It lasts 16-18 days (from around mid-September to the first Sunday of October) and is considered the world’s largest beer celebration event. On the other hand, Oktoberfest beer is any beer that is brewed specifically to be served at the Oktoberfest festival, which is mainly lagers.

Old ale

A type of strong ale. Most commonly, this term is used in England to refer to any dark beer with a malty flavor and an ABV of 5%.

Original gravity (OG)

The gravity reading of the wort that was taken before the yeast pitching and the start of the fermentation process. It will help brewers gauge the beer’s potential alcohol content. Also called starting gravity, starting specific gravity, or original specific gravity.


Adding priming sugar to the fermented beer using an excessive amount to carbonate the beer naturally. This results in gushing, or the explosive release of foam upon opening a beer bottle.


A chemical process where oxygen enters the beer after fermentation. This can result in a chemical reaction, which will, in turn, cause off-flavors in the beer.


Refers to the taste and aroma flaw in beer that can be perceived as winy, rotten pineapple sherry-like or a stale flavor like a paper or wet cardboard. It commonly occurs when oxygen is introduced after the fermentation process has been completed.

Oxalic acid

A colorless organic acid that is found in malt. It belongs to the carboxylic acids family. Also called ethanedioic acid.



Refers to the containers that are used for packaging and marketing beers and other beverages to the public. The most common types of packages commercially are cans and bottles.


The word referring to one’s sense of taste.

Pale ale  

A type of ale with a color that ranges from golden to amber. They are brewed using pale malts, hence the name, and ale yeast, are lightly hopped with a malty flavor, and moderately strong in general. They also typically have a 4-6% ABV range. The term was first popularized in 1703.


A protease enzyme that can be found in pineapples and papayas. In brewing, it is effective in reducing proteins in beer, thus providing clarity to the beer.


A heat exchange system that is used for heating or cooling large quantities of beer.


A process wherein the beer undergoes heat treatment at a temperature of 140-174 degrees Fahrenheit. This prevents the formation of and kills the microorganisms that could potentially damage the beer. It also prolongs the beer’s shelf life. It was named in honor of the French scientist Louis Pasteur. 


A common yet hard-to-remove bacteria or microorganism that causes spoilage to beer by producing high levels of lactic acid. It is sometimes considered desirable when brewing certain lagers, ales, and stouts. This is because they can produce Diacetyl, which gives the beer a buttery flavor and aroma. Brewers often shorten it to “pedio.” 

Permanently soluble nitrogen

Refers to the remaining nitrogen and protein compounds after the precipitation during boiling. These components are important in the creation of the beer head and also affect the beer’s mouthfeel.


An abbreviation that stands for “potential hydrogen” or “power of hydrogen.” It is used to measure the degree of acidity or alkalinity of a liquid solution using a logarithmic scale of 1-14. 0 is the most acidic, 14 indicates the highest alkalinity, and 7 is neutral. For a beer, the ideal pH level for it to be pleasant to humans is between 4.1-4.5.


A flavor and aroma in beer that can be described as medicine-like. clove-like, smokey, plastic-y, or like a band-aid. It is considered a flaw in most types of beer and is commonly caused by bacteria or wild yeast.


A type of lager beer that originated from Plzeň, a Bohemian city, where it also got its name. It is brewed using soft water, light-colored Pilsner malt, the noble hops Saaz and Hallertau hops, and Pilsner yeast. Pilsner is known for its light straw or golden color and flowery aroma. It has a crisp and lightly-hopped flavor with spicy, biscuity, and toasted notes, and a clean finish. Generally, Pilsner’s ABV ranges between 4.5-5%. This beer was first brewed by the Bavarian master brewer Josef Groll in 1842.


The brewing term for adding or pitching yeast to the wort before starting the fermentation process.

Points per Pound per Gallon (PPG) 

A unit that indicates how much gravity points one pound of malt contributes to a gallon of water.

Polymerase chain reaction (PCR)  

A method of testing that is used for yeast identification as well as in detecting any beer-spoilage microbes in the wort or beer by using a piece of DNA. It was invented by the American biochemist Kary Mullis in 1983.


A style of beer that was developed in the 1700s London, England. The Porter is noted for its dark color, which can range from medium brown to black. It is brewed using top-fermenting yeast and dark malt. Those impart the beer with roasted, caramel, and chocolate flavors with medium to high hop bitterness. Its name was derived from its popularity with river and street porters.


An abbreviation for “parts per million.”

Primary Fermentation

The first stage of the fermentation process after the beer has been brewed and the yeast has been pitched. In this process, the beer is kept sealed in a fermentation vessel for 1-3 weeks before being moved to another vessel for conditioning.


The process of adding priming sugar to beer to stimulate a secondary fermentation. It is also done to naturally carbonate the beer before bottling or kegging.


The legal ban on manufacturing and selling alcoholic beverages under the 18th Amendment. It lasted from 1920 to 1933 in the United States. Also known as “The Noble Experiment” because of its goals of eliminating alcohol abuse and reducing crimes.


A term that refers to the ethanol content in alcoholic beverages. This measurement equals 1.821 times the ABV volume in an alcoholic beverage. Although this term originated in England, the ABV standard is now used in the UK when measuring alcohol content.

Proteolytic enzymes 

These are enzymes that are produced by plants, animals, and bacteria. They break down proteins into nutrients and amino acids that are then used by yeast. They also leave some proteins that are responsible for the formation of the beer head, while enhancing the beer’s mouthfeel and richness.


The process where the proteolytic enzymes break down the proteins into amino acids. It occurs as one of the steps in the mashing processes, where the temperatures allow the proteolytic enzymes to be active.


Short for “public house”. An establishment that serves alcoholic beverages and where people gather, talk, and drink together. Synonymous with a tavern.


A person who owns and manages a public house or pub.


The term for the hollow indentation that can be found at the bottom of most liquor bottles. It increases the bottle’s strength and creates the illusion that the bottle contains more liquid than it actually does.



A word that means to drink deeply or thirstily. An example of this is when someone guzzles down beer heartily.


One of the phenolic compound subgroups can create stale off-flavors in beers as they can oxidize in the mash.



The process of transferring beer from one vessel to another, specifically during the packaging stage. This term is also used to describe transferring the wort from one fermenter to another for a second fermentation.

Racking cane

A tube device made of hard plastic that is used to siphon brew from one vessel to another.

Racking Port

Refers to the port located at the side of a vessel, particularly fermenters, that is used to transfer the beer to another container.


A type of beer with a distinctively smokey flavor due to being brewed using malted barley that has been dried over an open fire. It originated from Germany in the 16th century. In the modern age, brewers produce Rauchbier by using malt that has been smoked over beechwood. This results in a smoky flavor that is quite similar to that of hickory, earning the beer the nickname “bacon beers.” The name translates to “smokey beer.”  

Real Ale

A term for ales that the organization Campaign for Real Ale or CAMRA aims to promote. According to CAMRA, real ale has been brewed from traditional ingredients and methods. It should also undergo secondary fermentation. It is served using the same container that was used for the secondary fermentation. And lastly, it shouldn’t be infused with carbon dioxide or nitrogen. Bottle- and cask-conditioned beers fit the standards of being real ales, according to CAMRA.

Regional specialty brewery

A brewery that annually manufactures between fifteen thousand to six million barrels of beers. The majority of these beers are specialty beers.


A German law that literally translates to “purity order.” Passed in 1516, the German beer purity law requires that beers may only contain the ingredients barley, hops, and water. After the discovery by Louis Pasteur of yeast’s role in the fermentation process in 1909, it was added as an essential beer ingredient. It is considered the most famous law when it comes to beer brewing regulation.

Residual Alkalinity

A measurement determining the water pH’s resistance to any changes.

Residual Sugar

A term that refers to any sugar that the yeast did not consume during the fermentation process and still remains in the beer.



The conversion of starches into dextrins and fermentable sugars by enzymes. This occurs during mashing.

Saccharomyces carlsbergensis

An obsolete term for Saccharomyces pastorianus. See Lager Yeast.

Saccharomyces cerevisiae

A species of yeast that has been used in brewing, winemaking, and baking since ancient times. It is considered a top-fermenting yeast.

Saccharomyces uvarum

A bottom-fermenting yeast that is mainly used in brewing lagers and thrives the most at lower temperatures.


A type of Belgian pale ale that is light-bodied and highly carbonated, with spicy and fruity flavors. It undergoes a 90-day bottle-conditioning and has an ABV of 4.4-8.4%. It has its origin from the French-speaking region of Southern Belgium, Wallonia, and its name is the French word for “season.”

Saladin box

A device that is used for malting barley. It was named after its inventor, the French engineer Charles Saladin.


A taste or flavor like that of salt.

Scotch ale 

A type of beer that originated from Edinburgh, Scotland. These beers are top-fermented, lightly hopped, and are very malty, with sweet caramel or toffee flavors. They have varying strengths, with the ones with high ABV known as “Wee Heavy,” while those with low ABV are labeled as “Scottish Ales.”

Secondary fermentation 

A process that involves transferring fermented beer from the fermentation vessel to another vessel, and aging it for a long period of time that can range from two days to a few months.


The protein and yeast particles that settle down at the bottom of the fermentation vessel. They are either leftover from brewing or bottle-conditioning processes.

Session Beer 

Any beer that is light-bodied and has low alcohol content, generally around 3.2-5% ABV. They also don’t have high bitterness, hoppiness, or maltiness levels. Synonymous to low-gravity beer.

Shelf life

Refers to the amount of time that beer remains drinkable or fit for consumption. The shelf life of an unopened homebrewed or commercial beer ranges from six to nine months beyond the date on the label.


A plug that is usually made from wood or plastic. It is inserted into the hole on the top, curved side of a cask to fully close the bunghole after the cask has been filled.

Silica hydrogel 

A beer stabilizer that eliminates proteins and polypeptides from the wort by absorbing them. Those cause turbidity in beer, so using silica hydrogel helps to clarify the finished beer. It is also effective in extending the storage period of the beer by 180-240 days. 

Single Step Infusion    

A method of mashing where the water is heated a little bit above the target temperature, and then adding it to the mash to raise its temperature. The step is followed by stirring until the mash temperature of 148-156 degrees Fahrenheit is reached. It is usually the preferred mashing method of brewers just starting out with all-grain brewing.

Slack malt   

Refers to malt that has absorbed moisture after being stored and ends up being stale and soft.

Smoked malt

Malt that has been dried over an open flame to give it a smokey flavor that is needed for certain beer styles.

Soft water

Water that has low levels of magnesium, calcium, iron, and other minerals that harden waters. It has high levels of potassium and sodium and a low pH level, making it ideal to use for brewing light and crisp beer styles such as IPAs and Czech Pilsners.


A flavor and aroma flaw in beer that is similar to the taste and smell of acetone or lacquer thinner. It can be caused by high concentrations of fusel alcohol. Fusel alcohol is produced during high-temperature fermentation.


Sorghum Vulgare. A cereal grain that comes from the Poaceae family of grass. It is used in brewing African Sorghum beers and is popular amongst gluten-intolerant beer drinkers as it is free from gluten.


A vinegar-like, sour or sharp, acidic flavor in beer. It is sought after for beer styles that are intentionally sour such as Belgian lambics, Berliner Weisses, and Flander red ales. Still, it is seen as a flavor defect in most beers. It is commonly caused by bacterial contaminations from lactobacillus and other wild bacteria.


The method of spraying hot brewing water onto the spent mash grains. This maximizes the extraction of soluble sugars while avoiding the extraction of tannins. It is done after the lautering step. Sparge comes from the Latin word “spargere,” which means “to scatter ”.

Specific gravity 

The measurement of the wort and beer’s density compared to that of water, at a specific temperature. A hydrometer is used to measure Specific Gravity. Also known as present gravity.

Spent grains 

The leftover malt from the mashing process that has extracted sugars, starches, and nutrients from it for beer production. Also called “Brewers Spent Grain” or BSG.


A term used by brewers that is synonymous with fermentation vessel.


A type of carbohydrate that is present in a lot of plants, vegetables, sweet potatoes, and grains like wheat, rice, and maize. This polysaccharide gets broken down by enzymes during mashing. It then becomes the primary source of fermentable sugars for beer brewing.


The process of soaking the grains in liquid to extract flavors.


A device that is used to provide support for casks that are stored in a brewery.


A type of top-fermented British beer that is characterized by its dark, almost black color, heavy body, and distinctive roast flavor. The term “stout” was first coined in 1600s Britain. It was initially used as an adjective to describe strong Porter beers with an ABV of 7-8% but eventually evolved into a separate style of beer. Some examples of Stouts are Dry Irish Stout, Imperial Stout, Milk Stout, Oatmeal Stout, Pastry Stout, and Barrel-aged Stout.

Strike temperature  

The temperature of the hot brewing water or liquor that is used for creating the mash. It is around 167-176 degrees Fahrenheit (75-80 degrees Celsius).


Describes a flavor or aroma in beer that brings to mind sulfur, rotten eggs, or burnt matches. The most common source of this off-flavor is hydrogen sulfide. Hydrogen sulfide is a yeast byproduct when processing sulfur during fermentation.

Sunstruck beer

See Light-Struck.


A pleasant sugar-like taste or flavor.



Organic compounds that naturally occur in trees, plants, grain husk, hops, and some fruits like grapes. These are polyphenols that can produce a bitter, astringent off-flavor in beer. It can also create a chill haze that can turn into a permanent one, in higher concentrations.


A sharp, biting sour taste due to acids in beer.

Terminal gravity

See Final Specific Gravity.


A noble hop variety that is grown in the town of Tettnang, Germany, for which it was named. It is known as an all-purpose hop and for its distinctly floral and spicy character. Tettnanger hops have an Alpha Acid percentage of 4-5%. They are popularly used for bittering and adding aroma to German Pilsners, Belgian Pale Ales, and American Wheat beers.

Toasted malt

Pale malted barley that has been kilned for a specific amount of time to generate a toasty flavor.

Top fermentation 

A fermentation method that uses Saccharomyces Cerevisiae or ale yeast, and where the yeast rises to the surface of the wort. This method is carried out at high temperatures, around 68-70 degrees Fahrenheit (20-21 degrees Celsius). That is the optimal temperature range for the yeast to release flavor compounds. The beers that are brewed in this manner are called “ales” or “top-fermented beers.”

Trappist beer

Any beer that has been brewed by Trappist monks. They are members of the International Trappist Association (ITA) from the Trappist monasteries all over the world. Trappist beers are mostly top-fermented and bottle-conditioned. They usually have an amber or dark brown color, with a full-body and sweet, fruity flavors with a hint of spiciness.


A non-reducing disaccharide that provides yeast energy reserves for the yeast. It also functions as a stabilizer under stress, especially during high-temperature fermentation.

Trigeminal Nerves 

Refers to the nerves of the human face that sense texture and temperature. Some of the descriptors that can be used to describe beer sensations include hot, cold, tannic, astringent, silky, heavy, thin, dry, and cool.


A Belgian style of ale that is bright yellow to deep gold in color. It has a complex, yeast-driven flavor and aroma, a dense and creamy head, and a high alcohol content (ABV of 7% and up).


Refers to the layer of sediment consisting of proteins, hop debris, and other unfermentable materials. They form at the bottom of the fermenter after the fermentation process, and the wort has been racked to another container. 


A large container or vessel that is used for brewing, specifically in the mashing and lautering processes.


The degree of cloudiness in beer that is caused by sediments that remain suspended in the surface of the beer, resulting in a beer haze.



A conical vessel that combines the functionality of a fermenter and a bright beer tank. It is used for fermenting, carbonating, and conditioning the beer, mainly in large-scale beer productions.

U.K. gallon

The British measurement unit that is equivalent to 1.2 U.S. gallons. Synonymous with Imperial gallon.


A term that can refer to the empty headspace inside a keg, cask, or barrel, above the beer or to the beer residue at the bottom of a barrel after it has been emptied.

Undermodified malt

Malt that has a value of less than 35% in the Kolbach Index scale, which measures the soluble protein to total protein of the malt after modification. It has a lighter color and contains more starch compared to modified malt.


A term that describes a wort that has not been oxygenated sufficiently before fermentation.


Refers to the process of emptying the steeping vessel after the malt has been steeped.


Vicinal diketones (VDK)  

A group of flavor compounds that form during fermentation. This includes Diacetyl and pentanedione, which gives the beer a honey-like flavor. Excessive amounts of vicinal diketones in beer can indicate a bacterial or wild yeast infection and cause off-flavors in the beer.

Vienna lager

An Austrian style of beer that is copper to reddish-brown in color and of medium body. It has a malty aroma and flavor with a toasty note. Its bitterness level is on the low side, and its alcohol content is around 4.2-5.5% ABV. This beer style was released in 1841.


A wine-like flavor or aroma in beer.


The measure of a fluid’s resistance to flow or changing shape. Also often refers to the thickness of a fluid.


The yeast cell’s metabolism or activity. The yeast’s fermentation performance is linked to its vitality. A higher vitality translates to better fermentation performance.

Volatile Compounds 

Organic chemicals such as esters, fusel alcohol, and vicinal diketones, which affect the flavor and aroma of beer.

Volstead Act

The informal name for the National Prohibition Act. It is the law that enforces the Eighteenth Amendment. It prohibits the production, selling, and importing of alcoholic beverages in the United States. It was introduced to the House Judiciary Committee by House Chairman Andrew Volstead, for which it was named, and took effect in 1920. It was repealed in 1933.

Volumes of C02

A unit that measures the amount of carbon dioxide that gets dissolved in the beer. It also gives an indication of the beer’s carbonation level.


The German word that means “recirculation.” It refers to the all-grain brewing process where the wort is recirculated through the mash bed. This is done after the mashing process and before sparging.



A British colloquial term for alcoholic beverages, specifically beer. It is more common in usage in North East England.


One of the four essential ingredients in beer brewing, along with malt, hops, and yeast. It makes up about 90% of the beer or up. The water’s pH levels also affect the flavor of the beer.


A German term that refers to wheat beers that are top-fermented.

Wet Hopping

The technique of adding freshly harvested hops at any point in the brewing process. This method adds certain flavors and aromas to the finished beer, which are unique from those that dry hopping produces.

Whirlpool tank

A cylindrical vessel that is used for separating the trub from the wort. It swirls the boiled wort, allowing the trub to collect at the center of the bottom of the vessel, helping to clarify beer. Also called a hot wort tank.


A small plastic device that is placed inside a beer container to cause a rapid nitrogen gas release upon opening the container. It creates a long-lasting thick and creamy beer head.

Wild yeasts  

Yeast that naturally exists in the air or on the surfaces of trees, leaves, flowers, vegetables, or fruits.


A sherry-like flavor in the beer. It is usually a result of oxidation.


The sugary solution that is the result of the mashing and boiling processes. This solution will then be fermented into beer. Essentially unfermented beer.

Wort Chiller

A device that is used to cool the wort down to yeast-pitching temperature quicker than an ice bath method does.


Xylose (C5H10O5) 

A pentose (a monosaccharide with five carbon atoms) that is found within plants and cereal grains such as barley or wheat. When combined with another pentose, arabinose, they form the polymer called arabinoxylan. This polymer affects the viscosity of the wort.


Yard of ale  

A long, narrow glass shaped like a horn that is about 3 feet in height. It has the capacity to hold 2-3 pints of ale or beer.


Saccharomyces cerevisiae, a single-cell organism that thrives on moisture and warmth. It is one of the main ingredients for beer brewing. It is responsible for fermenting the wort into beer by converting the sugars into carbon dioxide gas and alcohol.


A flavor or taste that resembles that of yeast. It can be caused by suspended yeast in the beer.

Yeast Cake

Living yeast cells that have been compressed with starch to form a cake. The yeast cake will then be used in fermentation by dissolving it into the wort.

Yeast Enzymes

Refers to the enzymes that are inside the yeast cells. They do the work of converting sugars into alcohol. They also serve as catalysts for various activities that occur during fermentation.

Yeast nutrient

An additive for the boiling wort or fermenting beer to boost the health of the yeast and aid in yeast reproduction. It contains various nutrients and amino acids.

Yeast Pitching

The brewing step of adding yeast to the wort. It takes place before the fermentation process.



A traditional German unit of mass that is equal to 100 German pounds. In the UK commercial brewing industry, this unit is used as a standard measurement of hop weight. One Zentner is equal to 50 kilograms of hops. Its abbreviated form is Ztr. 


The yeast enzyme that serves as a catalyst for the fermentation process. The fermentation process then converts sugars into alcohol and carbon dioxide gas.


A beer-spoiling waterborne bacteria. These bacteria cause massive turbidity in beer. They also create off-flavors that are vegetable-like or like that of rotten apples.


It refers to the branch of chemistry that studies the science of fermentation in brewing.


The Greek word that refers to barley beer. It was initially used for referencing Egyptian beer.

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