Is whiskey brewed like beer? Whiskey is not brewed, but rather it is distilled. To brew is to prepare a beer, ale, stout, etc. by steeping, boiling and then fermenting or by infusing into hot water. Whiskey is not brewed, but rather, it is distilled. Distilled alcoholic beverages are made from fermented grain mash (a porridge-like substance). Different grains (which may or may not be malted) are used in different combinations and percentages to produce different variations on the whiskey. These grains include barley, corn, rye, wheat and oats. The stages of the distillation process are enumerated and explained below.
Stages of Distillation
- Mixing the mash bill
Explanations of the above stages:
Malting is a process in which grain is specifically treated to access its sugar. Grain is moistened and allowed to partially sprout, or germinate. The process of malting secretes an enzyme called amylase .The amylase converts the grains starches into sugars. The germination process is cut off when the grain is dried by heating.
Mixing the mash is mixing cooked grains with malted barley and warm water. After several hours, the mixture becomes a turbid, sugar-rich, porridge-like liquid known as mash. The mash is then put in a large tub called a mash tub. It is mixed with hot water and then agitated. Even if not making malt whiskey, some ground malted barley is typically added to help catalyze the conversion of starches into sugars. The mash is also sometimes referred to as wort. As much sugar as possible is extracted from the wort and it then goes on to the fermentation stage.
During the fermentation process, yeast is added to the wort. The yeast eats up the sugars in the wort and converts them into alcohol. The fermentation process takes place in giant vats, often called washbacks. Fermentation takes 48 to 96 hours. Different fermentation times and different yeast strains result in a wide spectrum of flavors in the final whiskey product. The resulting beer-like liquid (called “distiller’s beer” or “wash”) contains about 7% to 10% ABV (alcohol by volume) before it goes on to the still.
The process of distilling increases the alcoholic content of the liquid and brings out volatile components, both good and bad. Stills are usually made from copper, which helps remove unwanted flavors and aroma compounds from the spirits.
The two most common types of still are pot stills and column stills.
- Pot stills are usually (although not always) used in the production of whiskey from Scotland, Ireland, Canada and the U.S.A. Some styles use double distillation while others are distilled three times. The wash goes into the first still (often called the “low wines still”), where it is heated. Since alcohol boils at a lower temperature than water, the alcohol vapor rises off the liquid into the neck and lyne arm and then goes on until they reach the condenser, which turns into liquid again. This resulting liquid (which is about 20% ABV) then goes into a second still, called the “spirit still”, where the whole process is repeated. Sometimes the process is then repeated again for a third distillation. The resulting final spirit is about 60% – 70% ABV. The distiller discards a certain amount of the spirits from the beginning and the end of the run (known as “heads and tails”) because of their unwanted flavors and aromas. The rest (known as “the heart”) goes into barrels, often via a spirit safe. The bellows shape of the top part of the still makes the ethanol(alcohol) and water vapors condense, dropping down and rising again, thereby stripping out impurities.
- Column stills, also known as continuous or Coffey stills, are typically used to produce bourbon, rye and other whiskeys. They are also used in other countries such as Scotland, Ireland, Canada and Japan. The column still works continuously and efficiently, removing the need for the batch process used by pot stills. The distiller’s beer is fed into the column still at the top and begins descending, passing through a series of perforated plates. Simultaneously, hot steam rises from the bottom of the still, interacting with the beer as it flows downward, thus separating out solids and unwanted substances while pushing the lighter alcohol vapors up. As the vapors hit each perforated plate, they condense , thus eliminating heavy substances such as congeners while increasing the alcoholic content. Eventually the vapor is directed into a condenser. Column stills can produce spirits up to 95% ABV, although most whiskies are distilled to lower proofs.
- Hybrid stills (which include a column on top of a pot) can be used in either manner.
Maturation is aging. Almost all whiskeys are aged in wooden containers, usually oak. Some are new and some are reused from previous distillation or product. One exception to the maturation process is corn whiskey, which may or may not be aged. Bourbon, rye and other American whiskeys must be aged in new charred oak barrels. In other countries, the type of oak and its previous use are generally left up to the distiller. The filled barrels are then stored in warehouses. As the whiskey ages, some of the alcohol evaporates. This is known as “the angels’ share” and it creates a distinct and pleasant smell in the warehouse. Some whiskies, scotch for example, have a required minimum age.
Once matured (ages), whiskey is bottled at a minimum of 40% ABV. Whiskey may be chill-filtered or filtered in some other way to prevent it from becoming cloudy when cold water or ice is added to it. For most large whiskey brands, a bottling run combines a number of barrels (from a few dozen to hundreds) from the distiller’s warehouse. When only one barrel is bottled at a time, it is labeled as “single cask” or “single barrel”.
Malt Irish whiskey is made using 100% malted barley, distilled in pot stills. Single Malt Whiskey comes from only one distillery. Pot still Irish Whiskey is made from a mash composed of a minimum 30% malted and and minimum of 30% unmalted barley, with up to 5% of other grains. It is distilled in pot stills.
Irish whiskey is made from a blend of malted and unmalted barley in the pot phase. Scotch Whiskey, on the other hand, uses only malted barley. Irish Whiskey must be made in Ireland. Scotch Whiskey must be made in Scotland.