Distillation is the process by which a liquid is heated to create a vapor and then condensed back into a liquid again. The water mostly remains in the pot still (It is what you see in the left). All single malt whisky distilleries work with at least two series-connected pot stills. The first one, the wash still, distills the wash to 20% to 25% of alcohol. The resulting liquid is called “low wines”. The low wines are then transferred into the second pot still, called low wines still or spirit still, where they are distilled to an alcohol content of 65% to 70%. In the Scottish lowlands a lot of distilleries used to use a third still. This third pot still produced even purer alcohol at more than 75%.
Whiskies do not mature in the bottle, only in the barrel, so the "age" of a whisky is only the time between distillation and bottling. This reflects how much the cask has interacted with the whisky, changing its chemical makeup and taste. Whiskies that have been bottled for many years may have a rarity value, but are not "older" and not necessarily "better" than a more recent whisky that matured in wood for a similar time. After a decade or two, additional aging in a barrel does not necessarily improve a whisky. While aging in wooden casks, especially American oak and French oak casks, whisky undergoes six processes that contribute to its final flavor: extraction, evaporation, oxidation, concentration, filtration, and colouration. Extraction in particular results in whisky acquiring a number of compounds, including aldehydes and acids such as vanillin, vanillic acid, and syringaldehyde. Distillers will sometimes age their whiskey in barrels previously used to age other spirits, such as rum or sherry, to impart particular flavors.
Packaging And Exports
Most whiskies are sold at or near an alcoholic strength of 40% ABV, which is the statutory minimum in some countries – although the strength can vary, and cask-strength whisky may have as much as twice that alcohol percentage. Whisky is probably the best known of Scotland's manufactured products. Exports have increased by 87% in the decade to 2012 and it contributes over £4.25 billion to the UK economy, making up a quarter of all its food and drink revenues. In 2012, the US was the largest market for Scotch whisky (£655 million), followed by France (£535 million).