Single pot still whiskey


Single pot still whiskey is a style of Irish whiskey made by a single distillery from a mixed mash of malted and unmalted barley distilled in a pot still. Somewhat similar to single malt whiskey, the style was defined by its inclusion of unmalted raw barley in the mash in addition to malt. However, small amounts of raw oats or wheat may have been used at times. This unmalted component is said to give single pot whiskey a "spicier bristle" and "thicker texture" than the otherwise similar single malt whiskeys. If the whiskey is not distilled completely on the site of a single distillery, then it may be termed pot still whiskey but not single pot still whiskey.
Once the most popular type of whiskey in the world, this style of whiskey was historically referred to as pure pot still whiskey, Irish-style pot still whiskey, or – especially in Ireland – simply as pot still whiskey. The term "single pot still" was only introduced in recent years to overcome the United States Tax and Trade Bureau's objections to the use of the term "pure" in the labelling of food and drink.
The term should not be confused with the theoretical concept of whiskey produced solely in a pot still.

Science of Pot Still Distillation

To separate components from a mixture of liquids, the liquid can be heated to force components, which have different boiling points, into the gas phase. The wash is poured into a still usually made of copper and heated using steam. The wash consists of many chemicals, malted barley, alcohol, water, and sugar. The alcohol along with some chemicals needs to be separated. By using steam to heat the still alcohol and some volatile chemicals are evaporated first. As the gas travels upwards it is directed sent into another tube where cold water is constantly flowing around the tube. After the gas travels through the cold tube the gas is condensed back into a liquid and collected in a separate vessel. Depending on how the wash is turned in the still different chemicals are evaporated. A rummerger is used to constantly stir the wash to prevent burning of solid particles. After the first wash there is still 6-7% solids from the barley in the wash. During the heating process kinetic energy increases until they start to change phases. Then entropy increases from the phase change. In the cooling pipe kinetic energy and entropy both decrease resulting in another phase change from gas to liquid. In this process, not all of the solids are removed and some make it through the first distillation process.

History

Whiskey has been distilled in Ireland since at least the 1400s and most likely as early as the 6th century. Single pot still whiskey emerged as a means of avoiding a tax introduced in 1785 on the use of malted barley. Although this tax was later repealed, the popularity of the style endured until the emergence of blends in the late 19th and early 20th centuries.
In the 19th century, single pot still whiskey was the most popular style of whiskey in the world and formed the bulk of Ireland's whiskey exports. However, with the rise of cheaper, milder blended whiskeys in the 20th century, single pot still whiskey declined in popularity, and many formerly all-pot-still brands changed their production to become blends. By 1980, only two specialist bottlings remained in existence, Green Spot and Redbreast, with one in danger of being discontinued. However, in recent years, a resurgence in whiskey distilling in Ireland has led to the launch of several new single pot still whiskeys.

Legal definition

In addition to the general regulations governing the production of Irish whiskey, Irish government regulations stipulate that Irish pot still whiskey must be:
In addition, the regulation documents state that:
As of 2018, there are a handful of single pot still whiskeys on the market. However, due to the construction of several new distilleries in Ireland in recent years, several more single pot whiskeys are expected to be released in the coming years. Those available as of mid-2018 include: