What is Irish whiskey?

Whiskey may be called Irish Whiskey if it is distilled on the island of Ireland and has matured there for at least three years in wooden casks.

The requirements are set out in the Irish Whiskey Technical File, which the Irish Ministry of Agriculture submitted to the European Commission in October 2014. It also states that the distillate must leave the still below 94.8 percent alcohol, so that the aroma and flavour of the raw material are retained, and that bottling takes place at a minimum of 40 percent.

Pot still Irish whiskey is distilled in pot stills from a mash with at least 30 percent malted barley and at least 30 percent unmalted barley.

The unmalted barley is the feature that sets Ireland apart. The technical file attributes a spicy flavour and a creamy mouthfeel to that barley. Besides the two types of barley, a small share of other unmalted cereals may be included, such as oats or rye.

Single means that the whiskey comes from a single distillery, and that word can stand before pot still, malt and grain.

Single pot still is therefore pot still whiskey from a single distillery. Single malt Irish whiskey is made exclusively from malted barley from a single distillery. Blended Irish whiskey is a blend of two or more of the types pot still, malt and grain.

Triple distillation is customary in Ireland, but the technical file does not prescribe a number of distillations.

There are Irish distilleries that distil twice, and there are those that vary the number by type. What the specification does lay down is the upper limit of 94.8 percent when distilling, maturation of at least three years and the requirement that this maturation takes place on the island of Ireland.

Irish whiskey must mature on the island of Ireland and recognises pot still as a category of its own, whereas Scotch must mature in Scotland and does not recognise that category.

Otherwise the requirements are close together: both at least three years in wooden casks and both at least 40 percent at bottling. The Scotch Whisky Regulations 2009 recognise five categories, including single malt and blended Scotch whisky. Ireland has four: pot still, malt, grain and blended.

Whiskey with an e is the usual spelling in Ireland, and the protected name allows Irish Whisky as well as Irish Whiskey.

The full protected designation reads Irish Whiskey, Uisce Beatha Eireannach and Irish Whisky. An Irish bottler may therefore use both spellings. In Scotland, Canada and Japan, whisky without an e is customary; in Ireland and the United States it is usually whiskey.