It only takes a few days to distil a barrel of whisky, but it can take years of ageing for its flavour to mature.
Ageing whisky involves placing distilled spirits into wooden barrels and leaving them for a prolonged period of time, usually more than three years. Most whisky enthusiasts agree that well-aged whisky reigns supreme.
In general, older whisky is better. It’s easy to tell the difference between a whisky that has been aged for three years – considered the minimum ageing time for whisky – and one that has been aged for ten to fifteen years. Younger whisky is harsher, while aged whisky is smoother with a more complex flavour profile.
Why does aged whisky taste better?
It absorbs the flavour of its barrel
The barrel is an important factor in determining the flavour of whisky. Around seventy percent of a wood-aged spirit’s flavour is extracted from the barrel it is stored in. Usually these barrels are made of oak, however other woods are also used. Often the wood is charred, making it easier for the whisky to absorb its flavours.
Some of the liquid will evaporate
If whisky is aged in dry conditions, some of the liquid will evaporate over time, giving it a more concentrated and complex flavour. While whisky stored in humid conditions will still evaporate, it does so at a much slower rate.
Ageing whisky gets rid of harsher flavours
As whisky ages, its harsh flavours gradually break down. The wood of the barrel acts as a sieve, which traps forms of alcohol with larger molecules, such as methanol. This leaves behind a rich and flavoursome whisky. This is why younger whisky is often more bitter than older whisky.
Is it possible to age whisky for too long?
Most whisky enthusiasts agree that there is a point where whisky becomes too old. While you can buy whisky that has been aged for over fifty years – which often sells for up to $25000 a bottle – many suggest aiming for a middle-aged whisky, ideally one that has been aged for around six to ten years.