Acetaldehyde A by-product of fermentation resulting in a green-apple-like aroma.
Acidic Having a dry, or sour, taste, especially characteristic of fruity beers.
Additives Enzymes, preservatives and/or antioxidants that are added to clarify or preserve beer, or to improve head retention.
Adjunct Fermentable substance used instead of traditional grains to make beer lighter-bodied or cheaper.
Aerobic Characterizing the type of organism that needs oxygen to thrive. Top-fermenting yeast is an aerobic organism.
Alcohol Ethyl alcohol or ethanol, which is a by-product of fermentation.
Alcohol by volume Amount of alcohol in beer expressed as a percentage of total beer volume.
Alcohol by weight Amount of alcohol in beer expressed as a percentage of beer weight. Due to the specific gravity of beer, this value is typically 20% less than alcohol by volume.
Alcoholic Warming taste of ethanol and higher alcohol's.
Ale A type of beer brewed using top-fermenting yeast, which is usually stronger and more bitter than beer. The color can vary from light to dark amber.
All-malt A beer brewed exclusively with barley malt (i.e., no adjuncts).
Amber Beer characterized by a reddish-brown color, ranging from pale to dark.
Anaerobic Characterizing the type of organism that thrives without oxygen. Bottom-fermenting yeast is an anaerobic organism.
Aroma Another term for bouquet, defined below.
Aroma hops Varieties of hops chosen to enhance a beer's bouquet; also known as "aristocrat" hops.
Astringent Having tannic, sour notes, often due to boiling the grains, overly long mashes, or sparging with hard water.
Attenuation The degree to which the yeast ferments the wort during the brewing process.
B
Bacterial Having moldy, musty, or woody tastes due to microbiological spoilage.
Balance An important tasting concept describing the gestalt of elements in the bouquet and palate of a beer.
Balling Degrees Scale of the density of sugars in wort, developed by C J N Balling.