Aging / Maturation

After distillation, whisky is not yet drinkable, and is not even called whisky at this stage of the process. It is too high in alcohol, and must be aged for at least 3 years in casks before it can be called whisky.

The origin of casks

Barrels were discovered by accident, as at the time they were only used to transport whisky, which was consumed as is, without ageing. But it was a forgotten cask that led to the discovery of a spirit rich in aromas. Aging, particularly in oak casks, gives whisky much greater depth.

Oak casks

Oak casks are flexible and very robust over time, making them the best choice for maturing whisky without altering its character. There are several types of oak cask: American, which gives a spicier taste, European, which is woodier, and Japanese mizunara, which is finer on the palate.

The more porous the cask, the better the flavor transmission. What's more, it's generally old casks that have already contained another liquid that are used, as a new cask would alter the taste of the whisky too much. Today, most casks used are either ex-bourbon or ex-sherry.

Burnt Cask

The recovered casks are then burnt inside with an intense flame to increase the porosity of the wood and enhance the flavors. The carbon created by this burning acts as a filter and adds flavor. Barrels can be filled several times, often up to 4 or 5 times. The first fill is called the “first fill” and the second fill the “second fill”. Generally speaking, casks only add notes to whisky during the first two fills. To bring a cask back to life, a cooper scrapes off the burnt wood, then re-burns the cask so that it can be used again. This operation can be repeated up to three times per barrel.