As craft brewers continue to emerge and craft beer continues to grow in popularity, fans of these special brews may need to learn more about the terminology that a craft brewer uses. For instance, a variety of bars and restaurants now include detailed information about their craft beers on their menus. Do you know your ABV from your IBU? Here, we’ve briefly defined the terms that craft beer enthusiasts need to know:

ABV: ABV is “alcohol by volume,” the amount of alcohol in beer in terms of percentage.

Acetaldehyde: If you get a whiff of green apple aroma, it’s acetaldehyde, a byproduct of fermentation.

Adjunct: Adjuncts are the fermentable material used as substitutes for fermentable grains like rice or corn. They make beer lighter-bodied and usually less expensive.

Aerobic: Aerobics are microscopic organisms that need oxygen to metabolize, like top fermenting ale yeast.

Ale: Ales are beers made with top fermenting yeast strains, yeast that ferments at a higher temperature than the yeasts used to produce lager beer. The byproducts of top fermenting yeast strains – fruitiness and esters – may be part of an ale’s taste and appeal.

Amber: Amber refers to any top or bottom fermented beer with an amber color – neither pale nor dark.

Anaerobic: Anaerobics are microscopic organisms, such as bottom-fermenting lager yeast, that metabolize without oxygen.

Attenuation: “Attenuation” describes the extent to which yeast consumes fermentable sugars and converts them into carbon dioxide and alcohol.

Barrel: “Barrel” can refer to a measurement – a 31-gallon container of beer – or to an actual barrel or wooden container used to age beer and convey the flavors of the wood or the flavors of the barrel’s previous contents. In the United Kingdom, a barrel measures 36 imperial gallons.


barrel aged beer terms

Barrel-aged: A barrel-aged (or “wood-aged”) beer is any lager, ale, or hybrid beer that has been aged in a wooden barrel or in contact with wood. The intention is to impart the unique character of the wood or whatever has previously been in the barrel. Today’s craft brewers use mostly oak to influence the flavor and aromatics of a beer, but apple, alder, hickory, and a number of other woods may also be used.

Bitterness: The perception of bitterness in a beer’s taste – one of a beer’s defining traits – is caused by the tannins and iso-humulones of the hops.

Body: A beer’s “body” is its consistency and thickness. The sensation of a beer’s body in the mouth ranges from thin-bodied to full-bodied.

Bomber: A “bomber” is a slang term for a 22-ounce bottle of craft beer.

Bottle-conditioning: Bottle-conditioning is what happens to the beer inside the bottle – secondary fermentation and maturation – often forming more complex flavors and aromas.

Brewpub: A brewpub is a restaurant that brews and serves its own beers on the premises. A brewpub is known in Germany as a house brewery and in the United Kingdom as a home-brew house.

Boiling: Boiling is a critical part of the beer brewing process. Wort (unfermented beer) is boiled inside the brew kettle. During the boiling, hops are added to achieve bittering, hop flavor, and hop aroma. Boiling also removes dimethyl sulfide and excess or unwanted proteins in the wort. It sterilizes a beer and stops the conversion of proteins to sugars.

Carbon dioxide: Carbon dioxide created in the fermentation process gives beer its carbonation. As the yeast consumes the sugars in the wort, it creates alcohol and carbon dioxide.

craft beer definitions

Cask: A cask is a vessel or container for fermenting and serving beer. The beer is not force-carbonated at first, but it gains natural carbonation in the cask as yeast is introduced. Traditionally, “cask beer” is served slightly warmer than draft beer. Casks were originally wooden, but today most are stainless steel or aluminum. Casks are used particularly for cask-conditioned ales, which naturally carbonate. Craft brewers often add to casks ingredients like hops, chocolate, coffee, and vanilla beans.

Craft brewer: According to the American Homebrewers Association, an American craft brewer is a “small, independent, and traditional” brewer.

Draft (or draught) beer: Draft beer is the beer dispensed from a pressurized tank, keg, or cask.

Esters: Esters are the fruity, flowery, or spicy flavor compounds naturally created in fermentation. Esters are chemical compounds usually derived from a carboxylic acid and an alcohol.

Fermentation: Fermentation is the yeast action that converts sugars into ethyl alcohol and carbon dioxide.


beer hops

Hops: Hops are the little green flowers of the hop plant Humulus lupulus. They impart bitter, zesty, or citric flavors to beer. Only the female ripened flower is used. Almost all beer has some hops – the exceptions are rare and obscure. Hops added early in the brewing process gives beer bitterness, while hops added at the end provide additional flavor and aroma. Hops can taste like citrus, like flowers, or even like onions. Over a hundred varieties are currently cultivated around the world.

IBU: International Bitter Units – IBUs – are the measurements that indicate the “hoppiness” of a beer. The higher the IBU, the more the hops taste comes through. As almost every beer uses hops, almost every beer has an IBU count, but brewers often do not disclose the information on the bottles. Sometimes a high IBU is countered by a high malt presence that reduces the beer’s bitterness.

Keg: A keg is a measurement of beer equal to half a barrel or about 15.5 gallons. A half-keg – 7.75 gallons – is a “pony-keg.”

Lager: A lager is a beer produced with bottom fermenting yeast strains at colder fermentation temperatures than ales. Lagers typically have little or no yeast taste but taste fresh and clean.

Malt: Malt is processed barley that has been steeped in water and then dried in kilns to make it dry and ready for beer. Malt “extract” is a syrup or dry powder derived from malt and sometimes used in brewing.


microbrewery terms

Microbrewery: A microbrewery is defined as a brewery that produces 15,000 barrels of beer or fewer per year. Typically, most of a microbrewery’s sales are on-site.

Oxidation: Oxidation is a chemical reaction to the addition of oxygen or an oxidizing agent. In most beers, any oxidation is undesirable, since it can impart flavors of stale fruit (and worse), but in barleywines and stouts, oxidation can actually enhance flavor.

Session beer (or session ale): A session beer is a beer with a lighter body and less alcohol. Session beers are four percent ABV or less, so they’re appropriate when friends have a “session” and expect to drink more than just one or two. Be careful. Session beers or ales with friends can be great fun, but even with session beers, it’s possible to drink too much.

Tartness: “Tart” describes the taste sensation caused by sharp or acidic flavors.

Whale: A “whale” is a slang term for that special craft beer you want but cannot find anywhere. A “white whale” is a genuinely rare craft beer that may not be available or may be difficult to find and complicated and expensive to purchase.

Yeast: During fermentation, yeast converts natural malt sugars into carbon dioxide and alcohol. It is a micro-organism belonging to the fungus family.