What'll It Be? Bourbon Or Rye? Can You Tell the Difference?

May 17, 2019

When it comes to whiskey, you have your Bourbon aficionados and your Rye fans, and for many, it’s strictly one or the other.  But it turns out there are actually no dependably discernable taste differences between the two distilled drinks.  That’s according to a scientific taste test study by Virginia Tech Food Science professor Jacob Lahne. 

Dr. Jacob Lahne distributes sensory attribute reference samples to panelists during a whiskey study in Virginia Tech's Sensory Evaluation Lab
Credit Alex Hood

Jacob Lane started out as a ‘bourbon man’ but now, “I am omni bibulous,” a word that means he’ll ‘drink anything,’ and we both broke out laughing. We hadn’t even started drinking yet.

Well, we never actually started drinking. Lahne did this study a couple of years ago at U.C. Davis. So, no little glasses of brownish gold liquids to try and then pretend to spit out.  And as Lahne said, he doesn’t play favorites.  Actually, it’s all very scientific.  

“I do something called sensory science or some people call it sensory evaluation. And that involves, in a quantitative sense, how people perceive food; so how food tastes and smells.”

There’s a machine called a Gas Chromatograph Mass Spectrometer that can tell us what’s in a food or drink, but it can’t tell us what it will actually tastes like.  But he points out, humans actually have a great sense of smell, OK not as good as dogs, but better than machines at communicating about the nuances of flavor.  He gave a panel of volunteer tasters 24 different commercial whiskeys to sample and had them come up with words to describe them.

“And the reason for that is if I say ‘clove’ and you say ‘clove.’ We may or may not mean the same thing. I may be thinking cinnamon in my head.” So, the panelists would come up with terms they wanted to use to describe the whiskeys and references they shared.

But, after all that swirling and sniffing it turns out, that while people can certainly taste different flavors, they can’t reliably and definitively pick out which is rye and which is bourbon.

Lahne says part of the reason for the confusion is that “rye vs bourbon is actually a really narrow difference."  They’re produced in almost exactly the same way. The only difference is the raw ingredient so technically by law, the only difference is that bourbon has to be 51% corn and a rye has to be 51% rye grain.”  And to make it even more confusing, or nuanced, you might want to call it, “bourbon can (also) contain rye grain and rye can contain corn.

So, the question Lahne is exploring is, if they’re that similar in actual content, what accounts for the very real flavor differences between them. Well, that’s becoming the billion-dollar question with the huge growth in craft brews, from beer and wine to spirits.

“Bourbon and rye are big business,” says Lahne. It’s something like a 70% growth over the last ten years in the American whiskey market and it’s now between 3 and 4 billion dollars. Lahne remembers when the prized bourbon, ‘Pappy Van Winkle’ could be bought for under a hundred dollars a bottle a decade ago. Now it’s available mostly at auction and goes for many hundreds, more often thousands of dollars.  Some have termed it, ‘the bourbon everyone wants but no one can actually get.

And in that last 10 years there’s also been huge growth in craft distilleries. Mathew Bauer graduated from Virginia Tech 5 years ago with a hospitality and tourism degree and now he manages a distillery in Texas called Treaty Oak Distilling in Dripping Springs outside Austin.

He says, “Our mentality here is the ‘pursuit of the curious;’ Ttring to find niche parts of the industry and always trying to find out what drives people.”

Bauer says people are interested in the ‘art’ of it, the unique ways, boutique distillers age and blend their whiskey. The huge growth in the sector, apparently, is about, well, getting smaller.

“It’s not about big business anymore. I look at beer as the biggest example of this but it’s trickling down t all through the whole alcohol industry and through wine, beer and spirits.The big beers, (like) Budweiser, are not as pop as they once were and you see that they have seen that. So, they’re buying up all these little microbreweries; and that’s the cool thing that’s going on in America right now it’s all about the little guy.

An it’s also about nuance, precision and sometimes mystery. And Bauer is one of the few people who can address one musical mystery in the old Don McLean song, “American Pie.”  You know the line: And good ol’ boys were drinking whiskey and rye, singing this will be the day that I die…”

Rye, and bourbon are both whiskeys, so why would he such a meticulous wordsmith like Maclean have the good old boys drinking whisky and rye? Bauer says, you have to listen closely.

“It’s whisky in Rye and it’s Rye New York. I was born about 40 minutes from there.”  He says his father told him, having been to the bar in question.”  We have checked directly with McLean, but in song as in sprits, nuances matter.

Jacob Lahne and the Virginia Tech  Sensory Evaluation Lab are currently working on another tasting study, this time, it's whiskeys they distilled themselves, to find out more about where flavor actually comes from and why.