Water, Ice and Why They Matter

Should you add water? Is ice a crime? The honest answer is: it's your drink — but it helps to know what's happening in the glass.

Why a little water helps

Alcohol numbs the senses, and at cask strength it can hide flavour behind the burn. A few drops of water lower the strength and let more aroma escape. There's chemistry here too: a 2017 study from Linnaeus University in Sweden used computer simulations to show that when whisky is diluted to around 40–45% ABV, guaiacol — a molecule behind smoky aromas — tends to sit nearer the surface of the liquid, where it can reach your nose.

How to add water

• Use still, soft, room-temperature water — bottled spring water or a gentle tap water. Heavily chlorinated or mineral-rich water adds its own taste.
• Add it a few drops at a time with a pipette or straw, then nose and taste again.
• Cask-strength whiskies usually benefit most; a 40% whisky may need none at all.

Why it can go cloudy

If you add water to a non-chill-filtered whisky it may turn slightly hazy. That's natural fatty acids and esters coming out of solution as the strength drops — a sign of an unfiltered whisky, not a fault.

Ice

Ice chills the whisky, and cold dulls aroma and sweetness while emphasising bitterness and alcohol. As it melts it also dilutes, so the drink changes as you go. On a hot day, or with a young, punchy whisky, that can be exactly what you want. Whisky stones chill without diluting.

Mixing isn't a sin

In Japan, whisky is often drunk as a highball (with soda water and ice) or mizuwari (with still water and ice), and blends were made to be mixed. Save your rarest drams for neat tasting, and enjoy the rest however you like.

Next: how to taste whisky.