Common Brewing Terms

Adjunct

Any unmalted grain or other fermentable ingredient used in the brewing process. Common adjuncts are rice, corn, and wheat, but can also include any type of fermentable carbohydrate (e.g. honey, candi syrup).

Alcohol by Volume (ABV)

A measurement of the alcohol content of a solution in terms of the percentage volume of alcohol per volume of beer. Here's the formula for determining your ABV.

ABV =(76.08 * (og-fg) / (1.775-og)) * (fg / 0.794).

Ale

Ales are beers fermented with top fermenting yeast, typically within 65-75 degrees.

Alpha Acid

A measurement of hop bitterness. Equal to the weight in ounces multiplied by the percent of alpha acids.

Attenuation

The degree of conversion of sugar to alcohol and CO2. Used to determine how many sugars were fermented.

Barley

A cereal grain (similar to wheat and rye) that has been domesticated for use by brewers.

Body

The consistency, thickness and mouth-filling property of a beer. The sensation of palate fullness in the mouth ranges from thin- to full-bodied.

Esters

Volatile flavor compounds that form through the interaction of organic acids with alcohols during fermentation and contribute to the fruity aroma and flavor of beer. Esters are very common in ales.

Fermentation

The chemical conversion of fermentable sugars into approximately equal parts of ethyl alcohol and carbon dioxide gas, through the action of yeast.

Final Gravity (OG)

The specific gravity of a beer as measured when fermentation is complete (when all desired fermentable sugars have been converted to alcohol and carbon dioxide gas). Synonyms: Final specific gravity; final SG; finishing gravity; terminal gravity.

Head Retention

The foam stability of a beer as measured, in seconds, by time required for a 1-inch foam collar to collapse.

International Bitterness Units (IBU)

The measure of the bittering substances in beer (analytically assessed as milligrams of isomerized alpha acid per liter of beer, in ppm).

Lager

Lagers are any beer that is fermented with bottom-fermenting yeast at colder temperatures, typically 45-55 degrees F. Lagers are most often associated with crisp, clean flavors.

Malt

Barley that has been steeped in water, germinated, and later kiln-dried. This makes the starches in the barley available for conversion into sugars for fermentation.

Mashing

The process of mixing crushed malt (and possibly other grains or adjuncts) with hot water to convert grain starches to fermentable sugars. Mashing produces a sugar-rich liquid called wort.

Original Gravity (OG)

Gravity describes the concentration of malt sugar in the wort. The specific gravity of water is 1.000 at 59F. Typical beer worts range from 1.035 - 1.055 before fermentation (Original Gravity).

Phenols

A class of chemical compounds perceptible in both aroma and taste. Some phenolic flavors and aromas are desirable in certain beer styles, for example German-style wheat beers in which the phenolic components derived from the yeast used, or Smoke beers in which the phenolic components derived from smoked malt. Higher concentrations in beer are often due to the brewing water, infection of the wort by bacteria or wild yeasts, cleaning agents, or crown and can linings. Phenolic sensory attributes include clovey, herbal, medicinal or pharmaceutical (band-aid).

Saccharomyces (Yeast)

The genus of single-celled yeasts that ferment sugar and are used in the making of alcoholic beverages and bread. Yeasts of the species Saccharomyces cerevisiae and Saccharomyces pastorianus are commonly used in brewing.

Standard Reference Method (SRM)

An analytical method and scale that brewers use to measure and quantify the color of a beer. The higher the SRM is, the darker the beer. In beer, SRM ranges from as low as 2 (light lager) to as high as 45 (stout) and beyond.

Wort

The bittersweet sugar solution obtained by mashing the malt and boiling in the hops, which becomes beer through fermentation.

Zymurgy

The branch of chemistry that deals with fermentation processes, as in brewing.