Yes, Scotch Whiskey Is Better With a Splash of Water

By Carl Engelking | August 17, 2017 2:11 pm

(Credit: Shutterstock)

A true Scotch drinker doesn’t pour an aged Macallan in order to, as less refined revelers might say, “get the party started.” Quite the contrary, the seasoned aficionado attends to certain norms and customs before imbibing, not unlike a traditional tea ceremony, in a nod to enlightenment, restraint and discernment—the finer things.

The experts recommend pouring Scotch into a tulip-shaped glass to swirl the matured flavors. Sip, but never gulp, as that would be heresy to the history that’s sloshing around in your cup. And it is generally considered poor form to add ice; instead it’s better to add a splash of water to enhance the overall experience.

These seem like formalities meant to winnow the amateurs from the seasoned drinker, but science shows there’s a reason for this coordinated act—especially adding that splash of water.

Splash Science

Bjorn Karlsson and Ran Friedman of the Linnaeus University Center for Biomaterials Chemistry recently set out to explain why the splash of water seems to work.

The finest Scotch whiskies are known for their rich, smoky flavors. These signature notes are the product of phenols, or aromatic chemical compounds, in the whiskey. A particularly smoky phenol, guaiacol, is found in higher concentrations in Scotch whiskies than in American and Irish ones, because the malted barley used in the fermentation process is smoked over a peat fire. Guaiacol also happens to be active compound in an oral anti-cough medication.

Karlsson and Friedman narrowed their focus to the interplay of three primary ingredients in Scotch whiskey: water, guaiacol and ethanol. Then, they ran simulations that modeled the molecular composition of whiskey when the concentrations of these “big three” ingredients varied.

Ethanol, they discovered, grabs onto guaiacol molecules and clusters them together in clumps. When Scotch is distilled, ethanol concentrations reach 59 percent, and the aromatic guaiacol compounds are stuck to their partners throughout the liquid’s volume. Whiskey is then diluted, to roughly 40 percent, before it’s bottled, which causes ethanol to accumulate near the surface accompanied by guaiacol. When ethanol levels are diluted to 27 percent—say, when a Scotch drinker adds that splash of water—ethanol and guaiacol aerosolize, and those fragrant compounds waft into your nose.

Taste and smell, of course, go hand in hand, so it appears the right amount water will indeed enhance the flavors. However, there is a fine balance, as the authors write, “between diluting the whiskey to taste and diluting the whiskey to waste.” Too much dilution, and you lose that aerosolizing affect.

Fine Aromas

Gently sloshing Scotch in its glass jostles the other phenols in the liquid loose, further enhancing its aroma. And that tulip-shaped glass is designed to funnel those molecules into the nostrils where they are needed most. Put it all together, and these routines maximize the flavor in each sip—after all, some of the finest whiskies retail for hundreds of dollars.

Every whiskey is chock full of its own variety of aromatics and compounds that are unique to the location and manner in which it was bottled. Therefore, the optimal dilution will vary. And, to broaden our scope of spirits, researchers say, gin, rum and brandy can all be further enhanced with a little chemistry.

CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: chemistry
  • Dean Cleaver

    Please, can you correct your spelling. it’s Scotch “Whisky” not “Whiskey”. It’s a time honoured tradition that only whisky made in Scotland should have the spelling “Whisky” and “Whiskey” is generally for all other nations.

    • Martin Doležal

      My thoughts exactly. There is no such thing as “Scotch Whiskey”.

    • Erik Bosma

      And I always thought the Scots were good spellers.

      • Dean Cleaver

        They are. Carl Engelking isn’t :)

  • OWilson

    As a young man, I was fortunate enough to be working in East Fife with some real “Scot’s Whisky” aficionados, which is what they insisted it was called.

    The conversation which dealt with the dark arts of distilling was fascinating, and they all had their own ratings of the finest.

    Part of the “ceremony” was warming the glass at the end (it had to be bowl shaped, a la brandy but smaller) and one was supposed to hold the glass tightly to let the dregs run down the side of the glass for that most enjoyable, “last drop”.

    The only ice in those days was at the local fishmongers.

    (I can still reel off a list of the 45 most popular scotches, as a memory excercise!)

    • Uncle Al


      • OWilson

        I should mention that these guys weren’t lairds or thanes, and most had never seen a golf club.

        They were opencast coal miners and guys who ran the equipment. But they knew their history and the important stuff!

        (A very skeptical lot, by the way) :)

        • Uncle Al

          Youtube v=9vpqilhW9uI

          Cities are required to broaden perspective and embrace the future. A framer who questions what is obviously operative does not fare well. A farmer has no future, only a repeated year.

  • Uncle Al

    Lagavilin, Laphroaig, Ardbeg…Bruichladdich Octomore! The Macallan uses Golden Promise heirloom barley from patented seed and retained farmers. I view that as more of a style fetish than a bog craving.

    The epitome of dilution culture is the patient absinthe ceremony. Wormwood (Artemisia absinthium) is non-negotiable (e.g., Lucid Absinthe Supérieure), but definitely not greened with copper salts. Its bottle glass should be very dark, as the botanical colorants are light-sensitive.

    • OWilson

      From memory:

      Grant’s, Singleton, Abelour, Deveron, Laphfroig, Old Fettercairn.

      Ben Nevis, Glen Scotia, Loch Lomond (obviously)

      Oban, Tobermory, Arran, Jura, Scapa (the islands)

      J & B, Black and White, Haig and Haig (double barreled names)

      Ballantines, Cardhu, Lagavulin (heart of Johnny Walker Blends) Strathisla, Talisker (ladies whisky from the only distillary on Skye.)

      McCallan, Highland Park

      Glens: Livet, Keith, Fiddich, Elg, Ord, More, Kinchie, Morangie.

      Dalwinny, Balveny

      Mores: Ardmore, Dalmore, Cragganmore, Bowmore

      Belnds: Cutty Sark, Chivas, Dewars, Johnny, Bells, Famous Grouse,

      And the toast of East Fife in 1960 – Vat 69 (ymmv)

      The weird part is, I only drink Guinness, these days! :)

      • Mladen Vujović

        tell me, whos is Jameson?

        • OWilson

          Not on my list, but that would be Jamieson’s, an Irish whisky.

          Bushmills, Blackbush, Tullamore Dew are also good, they say!

          • Mladen Vujović

            yes, my mistake, and wanted to ask u about Tullamore Dew, nice to know, thanks a lot!

  • Erik Bosma

    I was a little disappointed in the article because they failed to mention anything about my favourite method of drinking Scotch – guzzling it. God, I used to love that stuff. Probably the reason I don’t drink it anymore.

    • David Clark

      Amen Erik, amen.

    • RS

      The article does talk about it. The first two paragraphs are about NOT guzzling it.

  • Bill Falkner

    The Scot’s make some of the best booze around. Nothing like a glass of Barrel Aged Scottish Ale. :)

  • andy kitts

    I’d take anything in this article seriously, if the subject of it was spelled correctly.


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