Cask Strength

Cask strength (also known as barrel proof) is a term used in whisky-making to describe the strength their whisky in the cask during maturation. This strong whisky is not the whisky that is usually bottled, as at cask strength the whisky isn't as drinkable. Most bottled whisky is normally diluted with spring water to bring its strength (ABV) down to a level that makes it more palatable, usually about 40 BV. This dilution is said to bring out the various flavours of the whisky; this is why distillers may dilute different whiskies to different concentrations.
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