Bourbon Glossary

Bourbon whisky, term by term.

179 terms and their meanings, drawn from the published JourneyM8 books.

179 terms

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ABV: Alcohol By Volume: ABV indicates the proportion of pure alcohol (ethanol) in a product relative to its volume. In many countries, including the U.S. and Scotland, spirits must not be bottled below a certain ABV, commonly 40%.
Age Statement: For many types of whiskey, including American, the age mentioned on the label refers to the number of years the youngest whiskey in the bottle has been matured in a cask.
Aging: The process of maturing whiskey in oak casks. While Scotch Whiskey has its own legal maturation requirements, American whiskey also has specific guidelines depending on the type, like bourbon or rye. c h o c o l at e b u tt e r s c o t c h
Aldehydes: Commonly associated with crops due to their presence in them. They exhibit a recognizable aroma reminiscent of freshly mown grass or leaves. Additionally, aldehydes often carry grainy, almond-like, or biscuity notes detectable from the glass. However, this pleasing aroma is typically found in limited amounts within whiskeys. Similarly, aldehydes can also convey minty, herbal, or dry scents.
American Single Malt: Must be made from 100% malted barley. Distilled at one distillery. Mashed, distilled, and matured in the United States. Distilled to no more than 160 proof. Aged in oak casks (not necessarily new oak, unlike bourbon). Entered into the barrel at no more than 125 proof. it won’t need to be distilled on a pot still and there is no minimum aging requirements. However, if an age is stated on the bottle, it must reflect the age of the youngest whiskey in the bottle.
American Standard Barrel (ASB): An ASB is a 200-liter cask commonly used to originally mature bourbon. These casks are typically made from American White Oak. c h o c o l at e b u tt e r s c o t c h
American Whiskey: Must be distilled from a fermented mash of cereal grain.Must be distilled to less than 160 proof (80% alcohol by volume).Must be stored in oak containers (not necessarily new).If aged for at least two years, it can be referred to as straight (e.g., "Straight American Whiskey"). If it's aged less than four years, the age must be stated on the label. No minimum aging period is required for American whiskey unless it's labeled as straight.
American Whiskey Maturation: For a spirit to be labeled as whiskey in the U.S., it must be matured in oak casks. Specific durations and conditions might differ based on the type of whiskey.
American White Oak: Also known as Quercus Alba, this oak species is native to North America and is well-suited for Whiskey maturation. It grows quickly, has tall straight trunks, and offers highquality wood with a rich presence of vanillins. Its flavor profile often includes notes of coconut, vanilla, honey, and nuts.
Amino Acids: Amino acids are compounds derived from proteins, which react with sugars (in Maillard reactions) during the malt process, resulting in the creation of color and flavor in the malt. b u tt e r s c o t c h
Amylase: Amylase consists of two major enzymes, a-amylase and b-amylase, along with limit dextrinase. These enzymes work together during mashing to break down starch into fermentable sugars like maltose and maltotriose, primarily at temperatures between 143-176°F. Angel’s Share: Refers to the amount of whiskey (a mix of ethanol and water) that evaporates from the cask during the aging process. The rate of evaporation can vary based on the climate, with warmer climates generally experiencing higher rates.

Backset: The liquid residue, or "stillage", that remains in the still after a distillation run. In the sour mash process, backset is added to the mash to ensure consistency and pH balance from one batch to the next. c h o c o l at e b u tt e r s c o t c h
Barley: A cereal grain that, when malted, provides enzymes to help convert starches to fermentable sugars. While it's a primary grain for Scotch Whiskey, in bourbon it's often used in smaller amounts to complement the flavor profile.
Barrel: The term refers to a standard unit of measurement which is 200 liters, or 53 gallons. It is also used incorrectly as a general term referring to any wooden vessel.
Barrel Proof: Whiskey that is bottled at the exact alcohol content it has when it's removed from the aging barrel. This means it's undiluted and offers a more intense flavor and mouthfeel. b u tt e r s c o t c h
Blended American Whiskey: A mixture which contains at least 20% straight whiskey or a blend of straight whiskies and, separately or in combination, whiskey or neutral spirits. A blended American whiskey is allowed to contain coloring, flavoring, or blending materials. If it contains at least 51% straight whiskey on a proof gallon basis, it may (but is not required to) designate the predominant type of straight whiskey (e.g., "Blended Rye Whiskey" if rye whiskey predominates by proof). The word "blended" must appear on the label. The percentage of straight whiskey contained in the blend must be disclosed on the brand label, unless the blend contains 100% straight whiskey. c h o c o l at e b u tt e r s c o t c h
Blended Straight Whiskey (or Straight Whiskey: A Blend): A blend of straight whiskies that does not qualify as blended American whiskey. This means that no neutral spirits, coloring, flavoring, or blending materials are included. The whiskies in the blend must be of the same type (e.g., all straight bourbons or all straight ryes). The product can be a mix of straight whiskies from different distilleries or states. If whiskies from multiple states are included, the label cannot make any claims about the specific state of origin. The label must clearly state the term "a blend" or "blended."
Bonded: Pertains to whiskey that has been stored in a federally bonded warehouse. This ensures it's aged a minimum of four years and, when bottled, it's at 100 proof b u tt e r s c o t c h
Bonded Warehouse: A bonded warehouse is a secure facility where dutiable goods can be stored or undergo manufacturing operations without paying duty (tax). Distilleries can store and mature Whiskey in bonded warehouses without paying duty until it's ready for bottling.
Bootlegging: Refers to the illegal production, distribution, and sale of alcoholic beverages during Prohibition in the United States (1920-1933). With the ban on legal alcohol, individuals and organized crime groups engaged in bootlegging to meet the demand for alcoholic drinks.
Bottled in Bond: A designation that requires the whiskey to be the product of one distillation season and one distiller at a single distillery. Aged in a federally bonded warehouse under U.S. government supervision for at least four years. Bottled at 100 proof. The bottle's label must identify the distillery where it was distilled and, if different, where it was bottled. c h o c o l at e b u tt e r s c o t c h
Bourbon: Must be distilled from a mash bill of at least 51% corn. Must be distilled to no more than 160 proof (80% alcohol by volume). Must be entered into the barrel for aging at no more than 125 proof (62.5% alcohol by volume). Must be aged in new, charred oak barrels. There is no minimum aging period for something to be called bourbon. However, to be labeled as "straight" bourbon, it must be aged for a minimum of two years. If aged less than four years, the age must be stated on the label. Cannot have any added flavoring, coloring, or other additives.
Bourbon Cask: Casks used for maturing bourbon are made from American White Oak and are charred before usage. These casks provide unique flavors that can influence spirits matured in them afterward. Bourbon itself is exclusively produced in the United States and must contain at least 51% corn in its grain mash. b u tt e r s c o t c h
Bubble Cap: A vital part of a column still, these are small caps on trays that allow alcohol vapors to pass through and interact with the liquid below. This ensures the vapors are properly refined before being condensed into liquid form.Bottled-in-Bond: A designation that ensures whiskey is the product of one distillation season and one distiller at a single distillery, aged at least four years under government supervision, and bottled at 100 proof.
Bung Hole: The opening in the head or belly of a cask used for filling and emptying. The position of the bung hole depends on the type of warehousing used.
Butt: A type of cask with a capacity of 500 liters, often used in sherry maturation. While its primary association is with sherry maturation, these casks can sometimes be used in American whiskey production, especially for finishes or specialty releases. c h o c o l at e b u tt e r s c o t c h

Canadian Whiskey: Often colloquially referred to as "rye" regardless of its rye content, Canadian Whiskey is a spirit distilled and aged in Canada, adhering to regulations set by Canadian law. It must originate from a mash of cereal grain, be aged in wood barrels of up to 700 liters for at least three years, be distilled to less than 94.8% alcohol by volume, and be bottled at a minimum of 40% alcohol by volume. While many Canadian whiskies incorporate rye grain, it's not a mandate, and the term "rye" historically denotes Canadian Whiskey in general. The blending of different grain spirits is a characteristic feature of Canadian Whiskey production.
Caramel Coloring: While some whiskies around the world use E150a caramel coloring to enhance color, it is not permitted in bourbon or straight American whiskies.
Cask: A vessel made primarily from oak used for maturing whiskey. Casks come in various sizes, with common ones being barrels and hogsheads, among others. b u tt e r s c o t c h
Cask Bung: A stopper used to plug the bung hole in the head or belly of a cask, typically made of wood or hard nylon.
Cask Strength: Cask strength Whiskey refers to Whiskey that has not been diluted after maturation and before bottling, preserving its full alcohol concentration.
Char: The result of burning the interior of a new oak barrel, creating a layer of carbon. This char plays a pivotal role in bourbon maturation, influencing color, flavor, and the smoothness of the final spirit.
Charring: The process of burning the inside surface of oak casks to influence the flavor and chemical structure of the whiskey. Charring allows for a deeper interaction between the spirit and the wood, enhancing the whiskey's profile. c h o c o l at e b u tt e r s c o t c h
Chill Filtration: Chill filtration is a method used to remove deposits in Whiskey. The Whiskey is chilled to between 14°F and 39°F before passing through a fine adsorption filter, mainly done for cosmetic purposes. A process to remove fatty acids, esters, and proteins to prevent the whiskey from becoming hazy.
Climate: Climate impacts the rate of Whiskey maturation. Warmer climates accelerate the aging process and increase the angel's share (evaporation).
Condenser: The condenser rapidly cools vapors coming from the still, helping to prolong complex chemical reactions taking place in the still and contributing to the flavor of the final Whiskey. Distilleries usually have a minimum of two condensers—one for each still—made of copper.
Congeners: Diverse chemical compounds, created during fermentation and aging, which greatly contribute to the complex flavors and aromas in whiskey.
Continuous Still: Also known as a column still or patent still, this type of still is used to produce grain spirits on a large scale. The spirit produced by the continuous still generally has a higher ABV than that from pot stills. While pot stills produce spirits batch by batch, a continuous still can operate constantly, making it efficient for significant production. Review:Russell’s Reserve Single Barrel Kentucky ABV%: 55% or 110 proof
Cooper: An artisan skilled in the age-old craft of cask-making. Coopers create and mend wooden barrels, crucial containers for aging whiskey.
Copper: Pot stills, commonly used in whiskey production globally, are typically made of copper. Copper is favored due to its malleability, effective heat conduction, and ability to remove unwanted flavors from the spirit. c h o c o l at e b u tt e r s c o t c h - 154-
Corn: Bourbon production predominantly relies on dent corn varieties, known for their characteristic indentation on the kernel. This type of corn is favored for its high starch content, crucial for fermentable sugars that lead to higher alcohol yields. While other grains may be part of a bourbon mash bill, by U.S. law, at least 51% of it must be corn, resulting in bourbons' signature sweetness and full-bodied flavor. The use of non-GMO and heirloom corn varieties is gaining traction among craft distillers, aiming to capture distinct and traditional flavor profiles. Outside the realm of spirits, dent corn is also used in livestock feed and various industrial applications due to its efficient starch-to-ethanol conversion.
Corn Whiskey: Made from a mash of at least 80% corn. Can be aged in new uncharred or used oak barrels. Distilled to no more than 160 proof and entered into the barrel at no more than 125 proof. Unlike other American whiskeys, it does not need to be aged. If aged, it must be done so at not more than 125 proof in used or uncharred new oak barrels. b u tt e r s c o t c h -155 -
Cut: During the spirit run, the portion of new make spirit selected for maturation in casks is known as the "cut" or "spirit cut," often referred to as the "heart."
Cut Point: The point in the batch distillation process when the spirit safe transitions from foreshots to heart (cut) and then from heart to feints. Distilleries determine the cut point based on the desired style of Whiskey. Traditional distilleries may use thermometers and hydrometers, while modern distilleries employ electronic monitoring devices.
Cytase: An enzyme that breaks down the cell walls of barley, making the starch accessible for the amylase enzyme to convert into maltose.

Date: 10th Dec 2023 Liquid Amber Vanilla, caramel, seasoned oak, baking spice, star anise, brown sugar, crème brûlée, toasted walnuts, toasted orange peel, and new leather. Cinnamon, baking spices, clove, vanilla, caramel, seasoned oak, brown sugar, clove, anise, cinnamon, red pepper flakes, leather, tobacco, baked apples, orange zest, mint. Rye spice, brown sugar, caramel, dry tobacco, brown sugar, chocolate, pipe tobacco, charred oak, and menthol. Non Chill-Filtered b u tt e r s c o t c h
Date: 9th Dec 2023 Amber honey Vanilla, toffee, and caramel, graham cracker sweetness, light smokiness, cigar box, and a hint of leather. Caramel chews and rye spice, leather, cereal grain, dark fruit, tobacco, and toffee. Rye spice, leather, oak, and black pepper. b u tt e r s c o t c h
Date: 10th Dec 2023 A rich spiced honey color. Sweet vanilla, sugar cookies, lemon frosting, worn leather, confectionery sugar, caramel, banana runts, dusty, vanilla, stewed plums, and hints of cherry. Rose, dried cherry, toffee, baking spices, caramel, cinnamon covered plum, dark fruit such as blackberry and apricot, and banana runts. Rich and earthy, lingering rye spice, with syrupy plum, oak, black peppercorn, and herbal notes. b u tt e r s c o t c h
Date: 10th Dec 2023 Burnished copper. Charred oak, flamed orange peel, oats, vanilla, burnt caramel, drip coffee, butterscotch, cocoa, and woody chunk charcoal. Orange zest, black pepper, tobacco leaf, honey, Werther's vanilla candies, caramel apples, molasses, cola, then allspice and nutmeg. Medium long, rye spice and pepper, cherry cola, dry powdered cocoa, and oak tannins. b u tt e r s c o t c h
Date: 10th Dec 2023 Deep Mahogany. Cherry candies, pink cotton candy, butterscotch, blackberry, pine tree, mulled wine, black pepper with a touch of smoky barbecue sauce. Raw sugar cane, candied cherries, stone fruit, freshly baked berry pie, buttery cinnamon, vanilla, dark chocolate, and baking spice. Medium long, stone fruit, baking spices, dry wine tannins, and a bit of spice. b u tt e r s c o t c h
Degradation: Refers to the breakdown of larger molecules into smaller ones during the germination process. c h o c o l at e b u tt e r s c o t c h
Dilution: After distillation, Whiskey is typically diluted from its initial ABV of around 65-67% to approximately 63.5% before maturation, and further dilution may occur before bottling.
Distillation: The technique of boiling a liquid, capturing its vapor, and then condensing that vapor back into a liquid. Alcohol has a lower vaporization temperature than water, so liquid alcohol turns to vapor at a lower temperature. This process concentrates the alcohol and flavor compounds in spirits like whiskey.
Distiller's Beer: The result after fermentation, a liquid containing alcohol and flavor compounds, which is then distilled to produce whiskey.Cooper: A highly skilled craftsman who builds and repairs oak casks using natural materials. Some distilleries employ larger cooperages for their casks, while others have their own cooperage on-site. b u tt e r s c o t c h Distiller’s Yeast: Specially bred and cultured yeast used in distillery fermentations.
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: The spent grain remaining in the mashtun after extracting the wort. It is often sold as cattle feed or used in biomass burners.
Dram: A Scottish term for a drink of Whiskey, also referred to as a nip or tot, though it is not an official unit of measurement.
Drum Maltings: A method of malting grains, including barley and rye, using large rotating drums. While traditional in some whiskey-producing regions, modern American distilleries may use drum maltings for efficiency and consistency in preparing grains for fermentation. c h o c o l at e b u tt e r s c o t c h
Dunnage: A traditional warehousing style where barrels are stored typically up to three high, usually characterized by thick walls and an earthen floor. Though more common in Scotch production, some American distilleries adopt dunnage-style storage for its purported impact on the whiskey's aging process.

Entry Proof: The alcohol strength, or proof, at which the freshly distilled spirit, or "new make", is transferred into barrels for aging.
Enzymes: Proteins that facilitate the breakdown or building up of other molecules in cells.
Esters: Chemical compounds primarily formed during fermentation when acids and alcohols combine, providing the fruity, vanilla, and herbal flavors and aromas in Whiskey. c h o c o l at e b u tt e r s c o t c h
Ethanol: Often simply referred to as alcohol, is the primary psychoactive ingredient that results from the fermentation process when yeast consumes sugars. Ethanol is a clear, volatile liquid that imparts the intoxicating effects associated with alcoholic beverages. During the distillation process of whiskey production, ethanol, along with water and various flavor compounds, is separated from the fermentation mash based on its boiling point, leading to a concentration of the alcohol in the distilled spirit. b u tt e r s c o t c h
European Oak: Also known as Quercus Robur. While this oak variety is prevalent in European spirit maturation, American distillers might use European oak barrels, especially for special editions or finishes, to introduce different flavor profiles, characterized by notes of spice and dried fruits.
Experimental Grains: The world of whiskey has seen a surge in experimentation as distillers look to differentiate their products and explore new flavor profiles. While corn, barley, rye, and wheat are the mainstays, several other grains are being trialed to produce distinctive spirits. Here are some experimental grains that distillers are exploring: Triticale, Oats, Millet, Quinoa, Sorghum, Rice, Spelt, Buckwheat, Amaranth, and Teff. Many of these experimental grains are being utilized by craft distillers who operate on a smaller scale and can afford to be more agile and experimental in their approach. As they explore these grains, they not only differentiate their products but also contribute to the evolving flavor palette of whiskey enthusiasts.

Feints: This is the term applied to the third fraction of the distillate received during the distillation of the low wines in the spirit still used in the pot still process of manufacture. The previous fraction of the distillate is the potable spirit. The cut point is judged by the stillman and is usually based on ABV. The feints are returned to the still, together with the foreshots. Feints are also known as tails. c h o c o l at e b u tt e r s c o t c h
Fermentation: The stage in the Whiskey-making process when alcohol is produced. Yeast converts the sugary wort into crude alcohol, resulting in a liquid similar to sour beer called wash.
Fill Proof: Synonymous with Entry Proof; it's the alcohol concentration when spirit is added to the aging barrel.
Filtration: Refinement of whiskey by passing it through a medium, often to eliminate unwanted particles or compounds, ensuring clarity and purity.
Finishing: The process of maturing spirit in one type of cask before transferring it to another cask of different origin.
First Fill/Fills: Refers to the initial use of a barrel for aging whiskey. In the American context, first-fill often indicates that the barrel has been previously unused or has been used for aging another spirit or wine. The fresh wood of a first-fill barrel has a pronounced influence on the whiskey, imparting stronger wood-derived flavors and characteristics. b u tt e r s c o t c h
Flour: The fine powder that makes up 10% of the grist used in Whiskey production.
Foreshots: This is the term applied to the first fraction of the distillate received during the distillation of the low wines in the spirit still used in the pot still process of manufacture. The following fraction of the distillate is the potable spirit. The cut point is judged by the stillman and usually based on time. The foreshots are returned to the still, together with the feints. foreshots are also known as heads.
Fusel Oils: Byproducts of fermentation, these are heavier alcohols which, in excess, can impart undesirable flavors and aromas to whiskey. These are often sold to other industries.

Germination: A stage in the malting process where grains, often barley or rye, begin to sprout. This is crucial for activating enzymes that will later convert starches into fermentable sugars. In the U.S., germination can take place in various settings, from traditional floor methods to modern commercial drums.
Grains: The foundational ingredients in bourbon production. While corn is dominant (at least 51%), other grains like rye, barley, and wheat may also be included.
Grist: After malting, malted barley is milled into a powder called grist, which must have a consistent texture to match the distillery's mashtun. The grist's composition is typically husk (20%), grits (70%), and flour (10%).
Grits: The coarser portion forming 70% of the grist.

Heads: Same as Foreshots. This is the term applied to the first fraction of the distillate received during the distillation of the low wines in the spirit still used in the pot still process of manufacture. The following fraction of the distillate is the potable spirit. The cut point is judged by the stillman and usually based on time. The foreshots are returned to the still, together with the feints. foreshots are also known as heads.
Heart: Same as Cut. During the spirit run, the portion of new make spirit that is kept for maturation in casks is called the cut or the spirit cut. It is also known as the heart. c h o c o l at e b u tt e r s c o t c h
Heel: The last bit of liquid at the bottom of a whiskey bottle, often saved by aficionados to compare with a new bottle.
High Rye Bourbon: Refers to a bourbon that contains a higher percentage of rye grain in its mash bill compared to the typical bourbon formulations. While all bourbons must contain at least 51% corn by law, the remaining percentage can be a mix of other grains. In the case of high rye bourbons, the proportion of rye is elevated, often ranging from 20% to 35% or even higher. This increased rye content imparts a spicier, more robust flavor profile to the bourbon, distinguishing it from bourbons with lower rye content that might be mellower and sweeter.
Hogshead: A cask made from bourbon staves with new oak ends, holding 250 liters. b u tt e r s c o t c h
Honey Barrel: Refers to a particular barrel of whiskey that, due to a combination of factors — including its location in the warehouse, the specific wood of the barrel, how it was treated, and other unpredictable factors — produces an exceptionally high-quality and flavorful spirit. Whiskeys from these barrels often have richer, more nuanced flavors that stand out from the average barrels aging alongside them. Distillers and blenders particularly cherish these barrels, as the whiskey they contain can elevate the taste profile of a batch or be bottled as a unique limited release.
Husk: The coarser part of the grain or barley forming 20% of the grist.
Hydrometer: An instrument used to measure the density of liquids, often employed to calculate alcohol content when combined with temperature readings. c h o c o l at e b u tt e r s c o t c h

Kentucky Straight Bourbon: Must meet all the legal requirements for straight bourbon. Must be distilled in Kentucky. Must be aged for a minimum of one year in Kentucky. If it's aged for two years or more, it can be called straight bourbon without specifying the age, but if it's aged less than four years, the age must be stated on the label. The term "Kentucky" in the name emphasizes the geographic origin and often indicates a particular quality and tradition associated with Kentucky bourbon production.
Kiln: A furnace or oven used for drying malted grains to stop the germination process. While peat is often associated with Scotch, American distilleries use kilns primarily fueled by gas or other means, ensuring the malt's moisture level is ideal for distillation.
Kilning: The drying phase in the malting process, where the germinated grains are subjected to heat in a kiln. This halts the germination and ensures the grains are dry and ready for mashing. b u tt e r s c o t c h

Lactones: Oak lactones are important flavor extractives in oak wood. The cis-isomer is usually dominant and imparts sweet vanillin and coconut aroma. The concentration of lactones varies between species, with the total amount of oak lactones being highest in Quercus Alba and lower in Quercus Robur.
Lautering: After mashing, the liquid portion (known as wort in brewing) is separated from the solid grain material in a vessel called a lauter tun.
Light Whiskey: Light whiskey is a category that includes spirits distilled to higher proofs (usually exceeding 160 proof or 80% alcohol by volume) using column stills. It's not as common as bourbon or other styles, but light whiskey can be produced with column distillation methods.
Lignin: A component found in oak that breaks down during toasting, creating flavor compounds such as floral, spicy, vanilla, and fruity notes during Whiskey maturation.
Lincoln County Process: In the production of Tennessee whiskey, the new make spirit typically goes through around 10 to 13 feet of sugar maple charcoal. This charcoal mellowing process helps to remove impurities and impart a smoother character to the whiskey before it is aged in barrels. c h o c o l at e b u tt e r s c o t c h
Low Rye Bourbon: Refers to a bourbon that contains a smaller percentage of rye grain in its mash bill relative to other bourbons. In low rye bourbons, the rye content is typically on the lower end, often less than 10% to 15%. As a result, these bourbons tend to exhibit a softer, smoother, and often sweeter profile compared to their high rye counterparts, with fewer of the spicy notes that rye typically imparts.

Malt: Grains, often barley, that have undergone germination and subsequent drying. This process activates enzymes essential for converting starches in grains to fermentable sugars. b u tt e r s c o t c h
Malt Whiskey: Must be made from a mash of at least 51% malted barley. Aged in new charred oak barrels. Distilled to no more than 160 proof and entered into the barrel at no more than 125 proof. If aged for a minimum of two years, it can be designated as "Straight," as in "Straight Malt Whiskey."
Malted Barley: Specifically barley grain that's been soaked in water, allowed to sprout, and then dried, releasing enzymes that play a pivotal role in whiskey fermentation.
Marrying: The process of blending two or more different whiskies together and allowing them to rest in a vat for a period.
Mash: A semi-liquid mixture made from combining milled grains with water, which sets the stage for the enzymatic conversion of starches into sugars. c h o c o l at e b u tt e r s c o t c h
Mash Bill: A tailored recipe specifying the exact types and proportions of grains used in the fermentation to produce distinct whiskey flavors.
Mashing: In American whiskey production involves combining milled grains with hot water in a mash tun or similar vessel. The heat and water activate enzymes (either present in the malted grains or sometimes added externally), which convert the starches in the grains into fermentable sugars. This sugary liquid, known as the "mash," is then cooled and transferred to fermentation vessels, where yeast is added to start fermentation.
Mashtun: This is the vessel where mashing takes place. It is made of cast iron or stainless steel. The bottom of the mashtun is effectively a sieve so that after mashing the wort (sugary liquid) can drain through to the underback before going onto fermentation. b u tt e r s c o t c h
Master Blender: The expert responsible for developing specific blended spirits by combining different whiskies with distinct characteristics.
Master Distiller: A senior position with various responsibilities, including managing staff, overseeing production, product development, quality control, product testing, and sourcing raw materials.
Maturation: In American whiskey, maturation refers to the aging process in which the spirit undergoes chemical reactions as it comes into contact with the wood of oak barrels. For many American whiskeys, including bourbon, the use of new charred oak barrels is a requirement. The duration of maturation can vary, and there's no set minimum aging period for bourbon, although to be considered "straight" whiskey, it must be aged for at least two years. c h o c o l at e b u tt e r s c o t c h
Methanol: A type of alcohol that is produced in small quantities during fermentation alongside the desired ethanol. Unlike ethanol, methanol is toxic to humans and can be harmful if consumed in significant amounts. During the distillation process, methanol has a lower boiling point than ethanol, so it typically comes off the still earlier, primarily in the "foreshots" or "heads" portion of the distillation run. Proper distillation practices ensure that this portion is separated and not included in the final whiskey product to keep it safe for consumption.
Milling: The process of grinding dried malt into a coarse flour called grist.
Moonshine: Traditionally, an unregulated and often illicit distilled spirit, typically clear and unaged, synonymous with "white lightning" or "mountain dew."
Mothballed: Refers to a distillery that has been temporarily decommissioned and is not producing. This term can be relevant for distilleries worldwide, including those in the U.S.

New Make Spirit: The initial, unaged distillate freshly collected from the still. Its clear nature and robust flavors have earned it the nickname "white dog."
No-age Statement (NAS): Refers to whiskies bottled without indicating its maturation age on the label. While it's become common in Scotch, the concept is also found in American whiskey, especially as producers release expressions that don't meet specific age requirements.
Nose: The bouquet of aromas emanating from whiskey, offering enthusiasts a preview of its flavor profile.
Nosing: The act of smelling Whiskey to identify flavors and aromas.
Nosing Glass: A specially shaped glass used for nosing Whiskey, available in various styles, with the Glencairn nosing glass or Copita style being common. c h o c o l at e b u tt e r s c o t c h

Oak: A robust wood, integral to whiskey maturation. Its unique properties infuse whiskey with color, tannins, and a variety of flavors.
Open Fermentation: A traditional method where fermentation occurs in vessels open to ambient air, potentially introducing unique wild yeast strains and flavors.

Peat: Rarely used in American whiskey production, peat refers to decomposed vegetation material. While it's commonly burned to flavor malted barley in Scotch Whiskey, its presence in American whiskey is an exception rather than the norm. pH: An essential metric in whiskey production, it gauges the acidity or alkalinity of a solution, impacting yeast health and fermentation efficiency.
Port Pipe: Some American whiskey producers use port pipes, which are casks traditionally used for maturing port, for finishing their whiskies, imparting unique flavors from the residual port. b u tt e r s c o t c h
Pot Still: A type of copper still used in batch distillation to heat up the wash and distill spirits, coming in various shapes that impact the character of the spirit.
Pot Still: A classic, often bulbous-shaped still used for batch distillation, valued for producing spirits with rich, robust flavors.
Prohibition Era: The period of time in the United States from 1920 to 1933 during which the manufacture, sale, and transportation of alcoholic beverages were banned. This nationwide ban was established by the 18th Amendment to the U.S. Constitution and enforced through the Volstead Act. The goal of Prohibition was to reduce societal problems associated with alcohol consumption, such as crime, poverty, and domestic violence. However, the ban led to unintended consequences, including the rise of illegal alcohol production and distribution networks (bootlegging), speakeasies (illegal bars), and organized crime. Prohibition ultimately proved to be difficult to enforce and widely unpopular, and it created a black market for alcohol. In 1933, the 21st Amendment was ratified, repealing the 18th Amendment and effectively ending Prohibition, marking a significant chapter in American history. c h o c o l at e b u tt e r s c o t c h
Proof: In the U.S., a measure of alcohol strength. It's double the alcohol by volume (ABV) percentage, informing drinkers of the spirit's potency.
Puncheon: A cask with a capacity of 500-700 liters, varying in size depending on its use, with sherry puncheons being larger than rum puncheons.

Quarter Cask: Typically 125 liters in size, made from 200-liter casks with a few staves removed and rebuilt, available in bespoke sizes. b u tt e r s c o t c h
Quercus Alba: American White Oak, it grows in North America. It is very suited to Whiskey maturation as the trees are fast growing with tall straight trunks meaning it is high quality wood with a high level of vanillins. It typically offers flavor notes of coconut, vanilla, honey and nuts.
Quercus Petraea and Quercus Robur: These are types of European oak. While they are not standard in American whiskey production, some distillers have experimented with these oaks for aging or finishing, resulting in unique flavor profiles. Racked, Racking: In whiskey production, racking refers to the careful transfer of whiskey between containers, be it from barrel to barrel or barrel to tanks. This process ensures consistency and quality in American whiskey production. c h o c o l at e b u tt e r s c o t c h

Raw Materials: These are the ingredients that go into bourbon. For traditional bourbon, the raw ingredients are yeast, a mix of grains (at least 51% corn), and water. Other grains commonly used in bourbon production can include malted barley, rye, and wheat.
Refill cask: In American whiskey, the common practice, especially for bourbon, is to use new charred oak barrels. Refill casks, or barrels that have been previously used to age whiskey, are less common in the U.S. but can be used for certain types of American whiskey not bound by the new barrel requirement.
Reflux: This happens during distillation. It occurs when some of the vapor meets a cooler surface inside the still and returns to liquid, falls back down the still and is re-distilled. It is a crucial element in the creation of each distillery’s unique character. Theoretically, more reflux means a lighter, more complex spirit. b u tt e r s c o t c h
Review: Stellum Blue Label Cask Strength KENTUCKY
Review: Old Soul Single Barrel High Rye Mississippi ABV%: 54.5% or 109 proof
Review: New Riff Kentucky Straight Rye Kentucky ABV%: 50% or 100 proof
Review: Milam & Greene Port Finished Rye Texas ABV%: 47% or 94 proof
Rickhouse: A specialized multi-story building used in the aging of bourbon and other American whiskeys. Within the rickhouse, barrels are stored on wooden racks, and the structure's design allows for natural air circulation and temperature fluctuations that influence the maturation process of the spirit inside the barrels.
Rye: A grain with a spicy kick, often incorporated into bourbon mash bills to provide a contrasting bite to corn's inherent sweetness.
Rye Whiskey: Must be made from a mash of at least 51% rye grain. Aged in new charred oak barrels. Distilled to no more than 160 proof and entered into the barrel at no more than 125 proof. If aged for a minimum of two years and meets other criteria, it may be labeled as "Straight Rye Whiskey."

Saccharification: This is the degradation of starch into simple sugars. c h o c o l at e b u tt e r s c o t c h
Single Barrel Whiskey: Each bottle of single barrel whiskey comes from an individual aging barrel, rather than being blended from multiple barrels. This can lead to variations between batches.
Small Batch Whiskey: While there's no strict legal definition for this term, it generally refers to whiskey that is produced by blending a relatively small number of barrels.
Sour Mash: A traditional method of pH control and flavor consistency in which a portion of previously used, acidic mash (backset) is added to a new mash. This process helps in maintaining a consistent pH level in the mash, controlling unwanted bacterial growth, and ensuring a consistent flavor profile from batch to batch.
Sourced: Refers to Whiskey purchased from a distiller by a third party and then bottled as a distinct brand. May be blended with other whiskies. c h o c o l at e b u tt e r s c o t c h
Sparging: Once the wort has been drained from the mashed grains, hot water is sprayed or poured over the grains to rinse out any remaining sugars. This ensures maximum sugar recovery and efficiency. Speakeasies were clandestine establishments that operated as hidden bars or nightclubs during prohibition. Since the sale of alcohol was prohibited, speakeasies offered a secret place for people to gather and consume alcoholic beverages. These establishments acquired their name from the practice of patrons needing to speak quietly or "easily" to avoid drawing attention to the illegal activities taking place inside. Speakeasies often required passwords or secret codes for entry, and they were known for their lively atmospheres with live music, dancing, and entertainment. b u tt e r s c o t c h
Spent Mash: Post-lautering, the residual grain material devoid of most of its sugars, often repurposed as animal feed.
Spirit Safe: This is a box-shape piece of equipment made of metal and glass which is padlocked. It connects to the point at which the spirit exits the still thus protecting the new make spirit coming off the still. Inside it there is a hydrometer and thermometer which lets the operator calculate the alcoholic concentration of the distillate without having to open the safe. There is a handle which can be moved from outside the safe to shift the spirit to the different receivers for the different cuts – foreshots, heart, feints. c h o c o l at e b u tt e r s c o t c h
Standard Barrel (American Oak): Approximately 200 liters (53 US gallon) - Often used to age bourbon before being repurposed for Whiskey maturation. The oak imparts vanilla, caramel, and sometimes coconut flavors to the Whiskey.
Steeping: The first step of malting where the barley grains are alternated, being soaked in water and then air-rested for a period of time to bring up the moisture level and initiate germination.
Still House: This is the building where the wash still and the spirit still are housed.
Straight Whiskey: Must meet all the requirements of its specific category (e.g., bourbon, rye, etc.). Must be aged for a minimum of two years in new, charred oak barrels. If aged less than four years, the age must be stated on the label. Cannot have any added colorings, flavorings, or other additives.
Straight Whiskey: A term denoting purity, it refers to whiskey aged for at least two years without any color or flavor additives.
Sweet Mash: When a distillery uses the term "sweet mash," it means that each new fermentation is started using a completely fresh batch of yeast, and there's no use of any previously fermented material (backset) from a prior distillation.

Tail Box: An integral component of a column still where heavier, later-stage distillates are collected.
Tails: The end fractions in a distillation run, typically containing heavier alcohols and often redistilled or discarded. b u tt e r s c o t c h
Tannins: These are naturally occurring compounds that exist in oak. They can add a chewy, dry mouthfeel to the Whiskey along with subtle notes of astringency and complexity to its flavor profile.
Tennessee Whiskey: While it often meets the criteria for bourbon, there's an additional step called the Lincoln County Process where the whiskey is filtered through a mellowing bed of sugar maple charcoal before aging.
Thief: An elongated, pipette-like tool that allows distillers to pull whiskey samples from aging barrels for evaluation.
Thumper: In American whiskey distilling, a type of pot still used for the second round of distillation. A thumper receives alcohol vapor, whereas a doubler receives spirit that has already been cooled into a liquid. c h o c o l at e b u tt e r s c o t c h
Tight Cut: A term signifying a distiller's precise cut, focusing only on the best, "heart" portion of the distillation run.
Toasting: The wood is heated up in a big oven for a period of time. This splits the cellulose into wood sugar which caramelizes and a portion of the lignin is converted to a number of compounds including vanillin.
Tun: A versatile term for a large vessel or container, often used in mashing or fermentation stages.

U-Proof: A specific proof or alcohol concentration used for tax assessment purposes in the spirits industry.
Uncut: Refers to whiskey that has not been diluted with water before bottling. Most whiskies have water added to bring them down to a desired proof or alcohol by volume (ABV) for sale. An uncut whiskey is bottled at the same strength or ABV as it comes out of the barrel, offering a more robust and intense flavor profile that reflects its natural state b u tt e r s c o t c h
Underback: A vessel used to store wort after it has drained from the mashtun and before transferring it to the washbacks for fermentation.
Unfiltered: Indicates that the whiskey has not undergone any significant filtration process before bottling. While many whiskies are chill-filtered to remove fatty acids, esters, and proteins to prevent the spirit from becoming hazy when cold, an unfiltered whiskey retains these compounds. As a result, it may offer a fuller mouthfeel and a more authentic representation of its character.

Vatted: Combining different batches of bourbon from multiple barrels but within the same distillery, ensuring consistency or creating unique profiles. c h o c o l at e b u tt e r s c o t c h

Warehouse: Often multi-storied structures where barrels of whiskey undergo aging, each floor can have varying temperatures influencing maturation.
Wash: Essentially "beer" without hops, it’s the name given to the liquid that is produced from fermentation. It has an ABV of approximately 7-9% and is then transferred to the wash still for the first distillation run.
Washback: This is the large vessel where fermentation takes place. They are usually made from Douglas fir or stainless steel.
Water Source: The specific origin of water, whether a spring, river, or well, crucial in whiskey production due to its mineral content and purity, affecting taste. b u tt e r s c o t c h
Wheat: A grain employed in some bourbons, recognized for imparting a gentle, sweet, and rounded flavor to the spirit.
Wheat Whiskey: Must be made from a mash of at least 51% wheat. Aged in new charred oak barrels. Distilled to no more than 160 proof and entered into the barrel at no more than 125 proof. If aged for a minimum of two years, it can be designated as "Straight," as in "Straight Wheat Whiskey."
Wheated Bourbon: A bourbon made with wheat as a dominant secondary ingredient. These whiskeys often have a delicate flavor and can be referred to as "wheaters." c h o c o l at e b u tt e r s c o t c h
Whiskey: A distilled spirit made from fermented grain and typically matured in wooden containers for some period of time. Whiskey can be made anywhere in the world. Certain countries—like Scotland, Ireland, the United States, and Canada—have regulations that govern its production. Also spelled "Whiskey."
White Dog: Also known as "moonshine" or "new make spirit," is the clear, unaged distillate that comes directly from the still after distillation. It serves as the base for many aged spirits, and when aged in oak barrels, it develops into whiskey or bourbon, gaining color, flavor, and complexity. b u tt e r s c o t c h
White Oak: Specifically, the Quercus Alba species, favored for bourbon barrel production due to its ideal flavor compounds and tight grain structure.
Wort: This is the name given to the liquid drawn off the mashtun which contains all the sugars of the malt.

Yeast: Essential microscopic organisms that consume sugars during fermentation, producing alcohol, carbon dioxide, and myriad flavor compounds.
Yield: A measure of production efficiency, indicating the volume of spirit distilled from a specific quantity of mash.

Zymurgy: The science and study of fermentation, a foundational pillar for creating alcoholic beverages like whiskey. This diagram helps visualise how these flavours sit in each Flavour Region in the mouth. For complex whiskies, its useful to consider which flavours you notice in the high palate, mid palate and low palate. HIGH PALATE: Almond, Apple, Citrusy, Lemon, Orange, Pine, Mint, White Pepper, Floral, Fresh Berries, Honey, Ginger, Marzipan, Nutmeg, Peppercorn, Green Tea b u tt e r s c o t c h LOW PALATE: Bitter, Dried Fruits, Dark Chocolate, Tobacco, Leather, Sherry, Wine, Seaweed, Wet Leaves, Bacon, Ham, Smoked Salmon, Port Wine MID PALATE: Baking Spices, Butterscotch, Buttery, Caramel, Chocolatey, Coffee, Fruity, Sweet, Vanilla, Grass/Hay, Malty, Creamy, Herbal, Earthy, Red Fruits, Toasted Bread, Milk Chocolate, Peaty, Woody, Nutty, Spicy, Toffee, Smoky

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