Home Brewing Lingo Terms & Definitions

Part of becoming a good brewmaster involves knowing a few terms which will help you better understand recipes and guides that talk about the brewing process. So nab yourself a notepad and pen and jot down the following terms or bookmark this page and come back to it at your leisure…

Adjunct – Unmalted grain used to brew beer. Normally used to refer to non fermentable sugars or other ingredients besides water, hops, yeast, and malted grains. 

Aerate – Mixing air and the wort to provide oxygen for the yeast.

Ale – Beer brewed using top fermenting yeast beer and warmer temperatures than Lagers.

All Grain – Beer brewing style in which the home brewer prepares the extract from grains as opposed to using extract prepared by a commercial company. It provides full control of the beer’s flavor and character.

Alpha Acid Units – Alpha acids are soft resins found in hops, which are used to bitter beer. The units are equal to the percentage of alpha acids times the weight. (example: 1 oz of hops X 12% Alpha Acids = 12 AAU’s)

Attenuation – Measure of the amount of sugars converted into alcohol during the fermentation process. This amount is found by measuring the specific drop in gravity from the original gravity using a hydrometer.

Barley – Grain used as the primary source of fermentable sugars and proteins for beer brewing

Beta Acids – Soft resins harsher in flavor than alpha acids also found in hops.

Bittering Hops – Hops used to add bitterness to beer during the boil. Usually hops with high amounts of alpha acids are used and must be boiled for 40-45 minutes or more to make them soluble.

Bittering Wort – Refers to the wort after it has been boiled and hops have been added.

Blow Off – Tube exiting from the fermenter used in place of an airlock to allow the release of Carbon Dioxide as well as unwanted hops and wort oils or other excess fermentation material

Body – The sensation of fullness of the beer in the mouth. Basically how watered down or good the beer feels.

Carboy – Fermentation vessel made of glass with a narrow neck.

Cold Break – When the proteins precipitate from the wort due to fast wort cooling. This helps avoid haze and cloudiness in beer.

Conditioning – A term used for either secondary fermentation or carbonation of beer depending on the style.

Decoction – Mashing method in which temperature is controlled from one stage to the next by taking only a portion of the mash, boiling it, and returning it to the mash tun.

Diacetyl – A fermentation byproduct that causes a butter or butterscotch like aroma and flavor which is cleaned up during secondary fermentation.

Diastatic Power – The enzyme potential of malt measured in degrees Lintner.

Dimethyl Sulfide (DMS) – Sulfur compound that contributes a sweet creamed-corn smell on Lager beers with low amounts of DMS. When in high levels it smells like corn, cabbage or other cooked vegetables. Low is good, high not so much.

Dry Hopping – Method of hopping to add aroma to beer after wort boiling, usually done during secondary fermentation.

Enzyme – In brewing terms, a complex proteing that can form or break other proteins or sugars.

Esters – A fruity smelling compound formed by joining alcohols and acids by yeast action.

Extract – Soluble material extracted from barley malt and adjuncts either by the mashing process or the malt extract sold by commercial companies.

Fermentation – The process where yeast cells convert sugars into one Carbon Dioxide molecule and one ethanol molecule.

Final Gravity (FG) – The concentration of malt sugar in beer measured after the first fermentation stage is complete.

Finings – Ingredients that help yeast, proteins and polyphenols to flocculate and settle out of the beer after fermentation improving clarity of beer.

Finishing Hops – Also known as aromatic hops, which are used to add aroma to the beer. Usually added during the last 5 minutes of the boil. Some add these during the last 1 or 2 minutes.  

Flocculation – The clumping of proteins and yeast cells that fall out of beer during fermentation.

Fusel Alcohol – Acohol with higher molecular weight of ethanol which causes harsh bitterness off flavors.

Gravity – The concentration of malt sugars in the wort. See also original gravity and final gravity.

Grist – Crushed malt and adjuncts being used for the mash.

Hopback – A filter made out of hops used to remove the break material from the wort.

Hops – Flowers of the humulus lupulus plant used to bitter beer and add flavor and aroma. Originally used as a preservative for beer and can be found in either pellets, plugs or whole leafs. See also Bittering Hops, Finishing Hops, and Noble Hops.

Hot Break – The clumping of proteins and tanins that fall out of the wort during the boil.

Hot Side Aeration – Aerating the wort while it is still hot which may cause oxidation.

Hydrometer – Tool used to measure the concentration of malt sugars in the wort. Used to get Original Gravity and Final Gravity.

International Bittering Units – Units used to measure bitterness of beer. One IBU equals one milligram of isomerized alpha acids per liter of beer.

Isomerize – The process of altering the arrangement of atoms by heating. Usually referring to the isomerization of hops to get the bitterness out.

Kiln – Furnace used to dry or roast malt using heat.

Krausen – A crown of foam that forms on the surface of the wort during fermentation. Sometimes used to prime, start a secondary fermentation or to hop beer.

Lager – Style of beer made using bottom fermenting yeast. Also refers to the process of storing beer at low temperatures and for longer periods of time to condition beer.

Lauter Tun – Vessel used to filter or sparge the wort from the grains after the mash.

Lovibond – Unit used to measure the color of malt.

Malt Extract – Sweet wort packaged in either thick syrup or dry powder. Used by homebrewers to skip the mashing process.

Malto-Dextrin – Refers to unfermentable sugars, usually used to increase body of the beer.

Maltose – Sugars preferred by yeasts during fermentation.

Mash – The process of converting grain starch into sugars by adding hot water.

Noble Hops – A set of hops known for their aroma characteristics and their 1:1 ratio between alpha and beta acids. These hops include Hallertau Mittelfruh, Tettnang Tettnanger, Czech Saaz, and Spalt Spalter.

Original Gravity – The measure of malted sugars in the wort which is measured right after the wort has been cooled after the boil and before adding yeast to ferment.

Points per Pound per Gallon (PPG) – The units of soluble extract of a malt when added to a gallon of water. It measures the change in specific gravity.

Racking – Transferring of beer from one vessel to another.

Sparge – The rinsing of grains using hot water during the lautering process. Also used to refer to the recirculation of wort.

Steeping – The soaking of barley grains to soften them and get sugars out for brewing.

Sweet Wort – Refers to the Wort before the boil and before hops are added.

Tannins – Polyphenol compounds found in grain husks or hop cones that can cause haze in beer.

Trub – The sediment formed by the hot break, cold break, hop bits and dead yeasts found at the bottom of the kettle.

Wort – Unfermented beer referring to the malt sugar in water. See also Bitter Wort and Sweet Wort.

Wort Chiller – Tool consisting of copper wire and hoses used to run water and chill the wort.

That pretty much does it for the most common terms you’ll see in the beer brewing world. If you come across other terms you are probably reading too much and are trying to become a chemist instead of a brewer. However if you feel I missed out an important definition I need to add to this home brewing lingo post, then please don’t hesitate to leave me a comment and let me know…