Should you add water to Whisky?

“Whenever someone asks me if I want water with my Scotch, I say I’m thirsty, not dirty.” – Joe E. Lewis

Whilst for many years it was anathema to add water to whisky, thereby ‘desecrating’ the most noble of drinks, in recent times the addition of a drop or two of water has become increasingly accepted amongst whisky lovers. In this post, we discuss some of the science behind the addition of water, although – as always – you should make your own choice based on personal preferences.

One key point to note, however, is that in many instances whiskies will already have had water added to them before being bottled, as part of a process called ‘cutting’ which is utilised to bring the whisky down to an alcohol content level which is more palletable for most consumers (think of your standard 40-46% ABV whiskies here, as opposed to cask strength examples which can be 60% ABV+).

Should you add water to Whisky

Should you add water to Whisky?

Why should you add water to Whisky? (Some science)

Probably the most noticeable difference when water is added to whisky is the change to the nose (smell). The combination of water and alcohol results in a slight exothermic reaction – one that gives off energy – and this actually slightly increases the temperature of the whisky in the glass. As the temperature increases (even very slightly) it releases more volatile molecules; those volatiles are the key to how whisky smells. In short, and perhaps paradoxically, the intensity of the nose of a whisky actually increases on first adding water.

Still, the majority of us drink whisky to taste it. Alcohol itself has an impact on flavour, and the higher the volume of alcohol (generally) the stronger the flavour – with more potent whiskies in terms of alcohol content sometimes obscuring more subtle flavours. Adding water slightly reduces the alcohol strength within the glass and opens us up to more salty and fruity tastes, as opposed to sweet and spicy flavours – although the type of water added (i.e. hard, soft, mineral for instance) and the amount will make a difference.

If you’re looking to examine the flavours and effects of adding water to whisky, then a couple of drops should be about right – although you can always add a little more if it suits your own tastes better.

Note, throughout this article we’ve been talking about whether you should add water to whisky, not ice! We cover the addition of ice in a separate article and explain some of the science behind it.