Glossary

ABV

Alcohol by volume; the measure of how much ethanol is contained in a given volume of a liquid, expressed as a percentage. See also Proof.

Aftershots

The final spirit produced from a spirit still at the end of the distillation process. These fusel oils are low in alcohol and can be discarded or redistilled. Also known as feints or tails.

Age statement

The number of years that distilled spirits have been stored in oak containers prior to bottling, as stated on the bottle. An age statement is required for American whiskeys aged less than 4 years. This also applies to blended whiskies if the youngest whisky in the blend has been aged less than 4 years. For nearly all whisky, the age statement must state the youngest whisky in the blend.

Angels' Share

The amount of liquid that evaporates from the barrel during the maturationprocess. This varies according to factors like heat and humidity, and the percentage lost is higher in warmer regions.

Backset

In American whiskey, an acidic liquid strained from the mash after the primary distillation. It's typically added back to the mash tub or fermenter to help catalyze fermentation and ward off bacterial contamination. Also known as sour mash.

Barley

A cereal grain used in the production of whisk(e)y. Malted barley is required to make malt whisky, although unmalted barley can be used to make other types of whisky.

Barrel

A general term for a type of wooden cask used in the storage and maturation of whisk(e)y. The term can also refer to standard units of measurement for different products in different regions. A standard bourbon barrel measures 200 liters, or 53 gallons. The Scotch Whisky Association defines an American barrel as measuring between 173 and 191 liters.

Barrel proof

Refers to whisky that's bottled at or very near itsalcohol strength when it emerged from the barrel at the end of maturation, undiluted by added water. In the U.S., TTB regulations require "barrel proof" whiskey to be bottled at not more than two degrees lower than the proof established at the time the spirits were gauged for tax determination. See also Cask strength.

Bere barley

One of the oldest varieties of barley in Britain, occasionally used for making malt whisky. These days, it's grown mainly in the north of Scotland, including on Orkney and Shetland.

Blend

A combination of two or more spirits. In the United States, a blended whiskey must contain at least 20% straight whiskey or a blend of straight whiskeys, while the remainder can consist of non-straight whiskey, neutral spirits, or both. In Ireland, a blended whiskey is a mixture of any two or more of the styles of malt, pot still, and grain whiskey. In Scotland, blended whisky is a mixture of whiskies from different distilleries, typically using both malt and grain whiskies. Blended malt whisky mixes single malts from a number of distilleries, while blended grain whisky mixes single grains from a number of distilleries.

Blended malt

In Scotland, a blend of malt whiskies from at least two distilleries; previously referred to as a vatted malt.

Bottled in bond

American spirits, most often bourbon or rye, produced within the regulations of the Bottled-in-Bond Act of 1897. These spirits must be produced in a single distillation season by a single distillery, mature in a U.S. bonded warehouse for at least 4 years, and be bottled at 50% ABV. Bottled in bond whiskey may also be referred to as bonded whiskey.

Bourbon

American whiskey made from a mash of at least 51% corn, with the remainder being any other grain. Rye and wheat are most common, and most contain a small amount of malted barley to aid in the fermentation process. It must be distilled to no more than 80% ABV, aged in charred new American oak containers with an entry ABV of no more than 62.5%, and bottled at no less than 40% ABV. Bourbon may be produced anywhere in the United States. For more information, see "Instant Expert: Bourbon, Rye, and American Whiskey."

Bung

The stopper used to close a barrel or cask.

Butt

In Scotch whisky, a cask measuring 500 liters.

Campbeltown

A whisky-producing region of Scotland, or a term describing whisky from this region. Historically a major center of distillation, Campbeltown now has only three working distilleries.

Canadian whisky

Often referred to as "rye" even when no rye grain is used in the whisky-making process. Canadian whisky may be made of any cereal grain and a finished product typically blends several types of whisky—such as wheat, corn, and rye—which are all milled, mashed, fermented, distilled, and matured separately. In addition, Canadian regulations state that Canadian whisky must be aged in "small wood" (less than 700 liters) for at least 3 years; undergo mashing, distilling, and aging in Canada; contain no less than 40% ABV; and possess the aroma, taste, and character generally attributed to Canadian whisky. Canadian whisky may contain added caramel coloring and flavoring; the law allows for up to 9.09% of the blend to be added spirits aged at least 2 years or wine. For more information, see "Instant Expert: Canadian Whisky."

Caramel coloring

A flavorless, odorless colorant made from sugar that darkens the hue of the whisky. It can legally be added to scotch and many other whiskies, but not to bourbon or straight American whiskeys. Sometimes referred to by the name e150a.

Cask

A general term for all types of oak vessels used in the storage and maturation of whisky. See also Barrel.

Cask strength

Refers to whisky that's bottled at the same alcohol strength it was when it was removed from the barrel; undiluted by water before bottling. See also barrel proof.

Charcoal mellowing

The act of filtering unaged whiskey through maple charcoal before going into the barrel—a requirement for Tennessee whisky. See also Lincoln County Process.

Charring

The act of burning the inside of a barrel as part of the coopering process. The amount of char impacts the color and flavor of the resulting aged whisky. Required for bourbon and Tennessee whiskey, among other American whiskeys.

Chill filtered

Refers to whisky that has been cooled and passed through a filter in order to remove particles that would affect its cosmetic appearance. Whiskies that do not undergo this process often advertise that they are non-chill filtered.

Chocolate malt

Malted barley that has been dried at higher temperatures, which darkens the color and releases cocoa flavors.

Coffey still

Refers to the column still design patented by Aeneas Coffey in 1830. A more efficient alternative to the pot still, it is capable of continuous distillation by reheating the liquid, rather than requiring distillation in batches, and can produce higher ABV spirits than pot stills. The device consists of two columns which contain a number of compartments separated by heated plates. The plates are perforated with small holes to permit the upward passage of steam and spirit vapor, which is condensed to become spirits. For more information, see "How To Make Whisky."

Column still

A more efficient alternative to the pot still, it is capable of continuous distillation by reheating the liquid, rather than requiring distillation in batches, and can produce higher ABV spirits than pot stills. The device consists of two columns which contain a number of compartments separated by heated plates. The plates are perforated with small holes to permit the upward passage of steam and spirit vapor, which is condensed to become spirits. Often referred to as a continuous still or Coffey still. For more information, see "How To Make Whisky."

Condenser

A component in the distillation apparatus that converts the spirits from a gas to a liquid through cooling, either as a coiled tube submerged in a tub of water (worm tub) or a vertical tube through which water is piped (shell and tube condenser).

Congener

Flavorful chemical compounds, including aldehydes, esters, acids, and higher alcohols, produced during fermentation and maturation.

Continuous still

Refers to the column still design patented by Aeneas Coffey in 1830. A more efficient alternative to the pot still, it is capable of continuous distillation by reheating the liquid, rather than requiring distillation in batches, and can produce higher ABV spirits than pot stills. The device consists of two columns which contain a number of compartments separated by heated plates. The plates are perforated with small holes to permit the upward passage of steam and spirit vapor, which is condensed to become spirits. Often referred to as a Coffey still or column still. For more information, see "How To Make Whisky."

Cooper

One who makes barrels or casks. Also refers to the process of making the barrels/casks, as in "coopering a barrel."

Cooperage

A business or premises that produces barrels or casks. Also sometimes used to refer to casks or barrels, e.g., "aged in new cooperage."

Corn

A grain used in spirits production. Corn is the primary grain in bourbon whiskey, required to represent at least 51% of the mashbill.

Corn whiskey

American whiskey made with a mash consisting of a minimum of 80% corn and distilled to a maximum of 80% ABV. Corn whiskey may be matured in used or uncharred oak containers, but does not require barrel aging. It is subject to regulatory requirements, setting it apart from moonshine. A variant known as straight corn whiskey is aged in used or uncharred oak barrels for 2 or more years.

Cut

The middle, best section of the distillate, often called the heart, which goes into the cask/barrel. Also refers to the process itself, i.e. "making the cut."

Distillation

The process of physically separating alcohol from water using heat. Alcohol has a lower vaporization temperature than water, so liquid alcohol turns to vapor at a lower temperature. The alcohol vapor is then recondensed to a liquid as it is cooled. For more information, see "How To Make Whisky."

Distiller's beer

The alcoholic liquid produced through fermentation that is then distilled to produce a spirit. It generally has 7-10% ABV. See also Wash.

Double-distilled

Distilling a spirit twice using a batch distillation method. Most Scotch malt whisky is double-distilled.

Doubler

In American whiskey distilling, a type of pot still used for the second round of distillation. A doubler receives spirit that has already been cooled into a liquid, whereas a thumper receives vapor.

Draff

A term used in Scotland for the remnants of grain drained from the wash following fermentation. Often used as animal feed.

Dram

A Scottish term for a glass of whisky; or a measurement equal to 1/8 fl oz.

Dunnage warehouse

A traditional warehouse, typically found in Scotland and Ireland, built with an earth floor and brick or stone walls.

Ethanol

A potable alcohol found in whisky and other fermented and distilled beverages, also known as ethyl alcohol. Produced as a byproduct of the fermentation of sugar by yeast.

Feints

The final spirit produced from a spirit still at the end of the distillation process. These fusel oils are low in alcohol and can be discarded or redistilled. Also known as aftershots or tails.

Fermentation

A metabolic process where yeast feeds on sugar, creating acids, gases, and/or alcohol as byproducts. All whisky-making includes a fermentation process before distillation.

Fermenter

The container in which mash is fermented with yeast into an alcoholic wash before distillation.See also Washback.

Finish

The aftertaste that lingers on the palate after consuming whisky. This is described both in terms of flavor characteristics and length. Can also refer to the process of cask finishing, where fully mature whisky is transferred from its original maturation cask to a different cask, usually for a short period of time, with the intention of imparting specific flavors onto the final product.

First-fill

A cask that has previously been used to age sherry, port, bourbon, or other aged wines or spirits, and is now being used to age another whisky for the first time. First-fill casks impart the most prominent characteristics of the previous liquid on to the whisky, while each subsequent fill will receive progressively less influence. See also Refill.

Flavored whisky

Whisky with additives, such as artificial flavoring or natural ingredients like fruit or honey, that change the taste. Often bottled below 40% ABV, the minimum proof for most whiskies.

Flavoring grain

In bourbon, refers to the secondary grain, such as rye or wheat, which has an effect on flavor profile if present in a large amount.

Floor malting

A traditional process where barley is germinated on a floor, turned by hand. Mostly replaced with more efficient modern processes like drum malting. The germination process converts barley's starches to fermentable sugars, and the process is stopped by drying with heat.