Malt whisky whisky regulations require malt whisky to be made in pot stills using water and malted barley without the addition of any other cereals, and the whisky must be aged for at least three years in oak casks. The use of new barrels is not required. Caramel coloring can be added, but no other additives are allowed. Irish whiskey regulations are almost identical to Scotch regulations. Malt whiskey must be distilled in a pot still from a mash of 100% malted barley, which may be peated or unpeated in character, although unpeated malt is typically used. All Irish whiskeys must be
Malt whisky mash of not less than 51% malted barley grain that is stored for aging in charred new oak containers at less than 62.5% ABV. If such a whisky has been aged for at least two years, contains no added coloring and flavoring, and has not been blended with neutral spirits or other types of whisky, the adjective "straight" can be applied, as in straight malt whisky. A blended whisky that contains at least 51% straight malt whisky may be labelled as blended malt whisky or malt whiskey – a blend. Canadian whisky regulations allow the addition of flavoring agents as