Ever so often I read about the almost mystical influence that water is supposed to have on whisky. But how big an influence can water actually have on the water of life? Let’s examine.

How Does Water Taste?

If you ask anyone on the street about the the taste of water, chances are you get a surprised look and the answer “Of nothing”. And most probably the person will doubt the seriousness of your question.

If you compare spring water samples though, you will detect differences. The mouthfeel of hard and soft water for example is noticeably different. Also there are fluctuations in taste caused by varying amounts of minerals. I am not talking about chemical additives to tap water like chlorine, by the way. Some waters can be slightly salty, some might have a bitter touch to them.

So there are noticeable differences, but to be honest, they only are very slight in most cases. Only some springs with extreme mineral content will display strong flavour notes.

What is Water Made of?

Another stupid question, I know. But it proves to be important nevertheless. Basically, regular spring water consists of H 2 O and the solved minerals during its journey through soil and rock. Anything else we definitely don’t want to have in our drinking water: heavy metals, pesticides, fertilizer and so on.

Drinking Water = H 2 O + Minerals

A Closer Look at Distillation

The main purpose of distillation is to separate the alcohol and aromatic components contained in the wash from the water. This is done by gradual heating of the liquid to slightly below 100° C, the boiling point of water. This works because fortunately the “good stuff” has evaporation temperatures below that mark. Due to the deliberate imperfection of a pot still, there still is a certain amount of water vapour finding its way through the condenser, so the process has to be repeated at least once to reach an alcohol content that is high enough that the spirit can be filled into casks.

Now what happens to the water during distillation? You can find the answer on your own, if you heat up some tap water in a pot and let it all boil away. You will be left with a grey residue made up from the minerals in the water. In the days before invention of ion exchangers, de-mineralized water was made by just distilling water.

During the distillation of whisky, the water in the still doesn’t even boil, so it will be fair to assume that the final spirit will contain pretty pure H 2 O in addition to the alcohol and aromatics. But even if some of the minerals can make into the spirit nevertheless, their effect on the flavour would only be minimal because the concentrated aromatics would overshadow it by far.

Take this and the fact that most whisky is diluted before bottling with regular tap water (without chemical additives, of course), and you will see that not much is left of the characteristics of the distillery water source.

Peaty Whisky From Peaty Water?

Now here’s a misconception that is about as persistent as the infamous Craig Shergold chain letter from the early days of the internet.

Every once in a while, newspapers, magazines or blogs inform us that the peaty character of Islay whisky is supposed to be an effect of the peaty water used in the distilleries.

Everyone who has at least a basic knowledge of whisky making should immediately know that this statement is pure rubbish. The water used by some Islay distilleries may well be peaty. But peaty water does not taste anything like peaty whisky. In fact the peat tastes more or less of nothing.

The phenolic flavours of peated whiskies are solely caused by the peat smoke that is used during the malting process when producing peated malt.

What is the reason for such misconceptions? I guess it is mainly because articles like this one are written by people who only have a semi-education about whisky. Usually it’s the “wine guy” of a newspaper or a general food blogger who does not properly research the facts they use in their articles.

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