Thursday, August 17, 2017

Whiskey, Water, and You

There has been a lot of coverage today of a new study that explains why dilution with water improves the taste of whiskey and other aged spirits.

In at least one instance, the article includes the dilution formula published in Bourbon, Straight (2004).

It is as follows:

(amount of whiskey) x ((bottle proof/desired proof) -1) = amount of water to add

There is, of course, always water in whiskey. Even a barrel proof bourbon such as Booker's is only about 63 percent alcohol, the rest is water. Most bourbon and practically all scotch is bottled at 40 percent alcohol and 60 percent water.

Some of that water, about 20 percent of it, remains in the distillate that leaves the still. More water is added to get the spirit down to barreling proof, which is 62.5 percent alcohol or less. After aging, more water is added to get the whiskey from barrel proof down to bottle proof.

The study authors write, "When whisky is diluted, the alcohol is driven to the surface, and many of the taste molecules follow it because they like to be in a slightly less aqueous environment." It is unclear if this is something immediate, that happens right after water is added and then dissipates, or if the alcohol stays in that state. And, if it does, does the same thing happen when you pour diluted whiskey into a glass? Or do you have to add more water to create the effect?

It sounds like it happens each time you add water, up to a point of diminishing return. The authors also make an argument against cask strength whiskey that doesn't seem to comport with the experience of most drinkers, who find high proof whiskey very flavorful.

Ice, of course, makes the liquid cooler and also dilutes it, continuously as the ice melts.

Some people believe you should drink whiskey at bottle proof because that is what the maker intended, but this isn't necessarily true for barrel proof (i.e., cask strength) whiskey. The idea of a whiskey straight from the barrel is so you don't have to pay for added water and can dilute the spirit to your taste preference.

That is the best rule anyway. Find out what alcohol concentration you like best and stick to that. Your personal preference is all that really matters and you have all the diagnostic equipment you'll ever need right there in your head.


Erik Fish said...

I have gotten divided reactions from other whiskey drinkers to my theory, but I have become convinced that barrel-proof or high-proof whiskey, poured and diluted down a few minutes before drinking, is more flavorful than the same stuff already down-proofed before bottling, even if both are drunk at the same proof. I've made the comparison with Scotch (Laphroaig), Irish (Redbreast), and American whiskeys (most recently 1792 Barton) where the same expression/age is available as cask-strength as well as drinking strength bottlings.

Some fellow drinkers who've done tasting with me think I'm full of hooey, but my brain as informed by my nose and palate is convinced it's a thing. And if I understand the study correctly, it supports my contention scientifically.

Jim Laminack said...

In my line of work I often conduct whiskey tastings in an educational format. I always have the participants drink it neat first then add 2 drops of spring water (I supply dropper bottles for this). It is amazing to taste the immediate difference. I have been at a loss to explain why this phenomenon occurs until now.
Thank you Chuck!

Sam Komlenic said...

The authors of the study also 9nitially stated that "whiskey" with an "E" is made from water and malted barley (essentially Scotch). I see that has now been changed to water and grains to more fairly accommodate other styles of whiskey.

I stopped reading the article at that point. Inaccurate input leads to inaccurate output.

Chuck Cowdery said...

Blame the reporter, not the study authors. Also, you quit before the best part ... ME!

mr manhattan said...

So I sell American whiskey in a bar that specializes in this spirit (i.e. we sell no other kind if whiskey). We offer folks the option of adding water (using a dropper bottle) to suit their taste and preferences. I see people add varying amounts of water, from the proverbial “drop” to several droppers-full. And I have heard all sorts of explanations for why this does or does not matter. I have my own ideas, of course, but unless asked, I keep these to myself. I mention all of this only to establish that I have spent a lot of time both thinking about the “whiskey in water” question and watching people’s response to adding it.

My conclusion is that the only study that probably matters is one that takes into account the subjective nature of sensory evaluation and the psychology of the subject. Someone who believes that adding a single drop of water to a solution that contains better than 60% ethanol is going to significantly change the physical structure of that solution is going to “notice a difference” no matter what.

The study in question focused only one particular congener (guaiacol), which is apparently hydrophobic in nature (i.e. does not like to stay dissolved in water). The study showed that when the whiskey is diluted in a very controlled fashion, causing the ethanol to rise to the surface, the guaiacol will follow it, were it can be more easily detected by the nose. However, whiskey contains a entire bestiary of congeners of varying classes and each will behave a little differently. I wouldn't make any significant conclusions except perhaps to say that under the right conditions, a little water might make some whiskies smell smokier.

Crown Point Marc said...

I'm not sure about improving the taste of whisk(e)y, but I do notice a difference between one with a teaspoon of water and the same without water. It depends on the whisk(e)y if I prefer it neat or with a splash; possibly my mood also.

Brian (AKA The Dean) said...

As a longtime research professional, I try to refrain from drawing any conclusions from a cursory report, on a single study. Show me the methodology, collection method, raw data, etc. and body of previous/subsequent research, and then. maybe, I can draw and educated conclusion.

With that said, while I may taste a bourbon straight, I virtually always drink it on the rocks. I simply like my whiskey very cold. Depending on the whiskey (proof, profile, etc). the situation, my mood, environment---(and how much I plan to drink), I'll add varying amounts of water. But I have to say, I've never considered measuring the amount of water I add with an eye dropper (or any particular measuring device. My eye works just fine. I'm not judging. Everyone is entitled to their own taste and method.

With that said, I do understand why you may want to control all the variable for official tastings (or in an educational environment). But simply for drinking? Really?

Jon Hamre said...


With that said, I do understand why you may want to control all the variable for official tastings (or in an educational environment). But simply for drinking? Really?

I think for me this is the thing about the whole article that rubbed me the wrong way, the gist of it was pretty much that anyone drinking whiskey neat or straight out of the bottle was a fool for doing so. It goes without saying that as you adjust the ABV you will see different characteristics come through as you go down, but to say that doing so is the only way to truly get the most out of a dram seems silly.

Perry Huntoon said...

I discovered the difference a few years after a tour at the Barton distillery in Bardstown. The guide had us sample 1792 neat and then had us add just one drop of water. It was an amazing difference as that one drop seemed to really open up the flavor profile of the bourbon.