Presented unedited other than formatting; this was written back in October 2001.
>>
Adding water to whisky
I was very dubious about this for a long time, but there *is* a scientific reason for it. It goes something like this:
The naturally occurring chemicals which are responsible for the flavours of whisky are of two sorts, hydrophilic (“water loving”) and hydrophobic (“water fearing”, these are the more oily components). Bottle whisky is generally of the order of 43-45% alcohol, the rest being water, with the flavour components present in trace amounts, and the whole lot forms a glorious homogeneous solution.
When you add water, you’re changing the water:alcohol balance (fairly obviously). This has the effect of repelling a proportion of the hydrophobic flavour components OUT of the solution. What happens is they escape as vapour into the space above the glass. Since a large proportion of our sense of taste is actually linked to our sense of smell, what happens is that our noses detect the extra vapour, and the taste of the whisky is enhanced.
However, whisky that’s diluted with water should not be allowed to stand, because over time the new vapours above the surface will diffuse away with the end result being that you’ve lost a lot of the flavour components.
The best results, I find, come when you add a small splash of water to the whisky, and drink it from a nosing glass, which is designed to funnel the vapours towards your nose. “A small splash” can be anything from a few drops to about 25% (volume:volume) – anything more really does tend to dilute the flavour components a bit too much unless it’s a particularly powerful whisky. But experiment with the flavours before and after adding water. A particularly vapoury malt such as 10-year Ardbeg leads little or no water adding, whereas some of the older more deeply-flavoured malts (the Glenmorangie special finishes come immediately to mind) benefit quite amazingly from a moderate sized splash.
</chemist>