Fooling Father Time: ‘Rapid-aging’ and the future of craft whiskey

The standard formula for whiskey, the way it’s always been done, is this: you fill up an oak barrel with a clear spirit and then you wait. And wait. And wait.

Inside that barrel, things slowly unfold. Alcohol seeps into the toasted oak, degrading the polymers that make up its structure. The lignin and hemicellulose in the wood release some potentially tasty molecules. Esters form, then break apart, then recombine. Oxygen changes the liquid and evaporation concentrates it. A long series of chemical changes makes the spirit deep, flavorful, and smooth.

And the most important ingredient in all of this is time—that cruel, immovable force—the measure by which spirits are often appraised. In the heat of Kentucky, a bourbon might spend four to eight years aging before it’s deemed ready. In the more moderate climate of Scotland, a single malt may take 12 years to really hit the sweet spot.

This timeline is a problem for small craft distillers—it costs a tremendous amount of money to distill a whiskey, fill some barrels, and let that overhead sit in a warehouse for a decade. What can a distiller do about it? Perhaps they make a gin or a vodka to keep the lights on while their whiskey is maturing. Or maybe they get impatient and sell some expressions of “young” whiskey—with a year of age or less—but risk hurting their reputation by selling a spirit before it’s had a chance to mellow.

Iron Range Single Malt finishes aging at Vikre Distillery

It’s this struggle that’s led certain distillers to explore the science of aging and find ways to accelerate it. They’re developing strategies, both low-tech and highly intricate, to get their whiskies ready in only a few years, months, or even weeks.

Some try manipulating the barrel’s environment—it’s well known that shifts in temperature, humidity, and atmospheric pressure affect the way a barrel “breathes.” Some distillers send their barrels to high elevations (Montanya Distillers), others out to sea (Jefferson’s), or even under it (Seven Fathoms Rum), though these strategies provide more of a great marketing story than a truly innovative whiskey.

A more common strategy is to increase the spirit’s contact with oak. Many distillers simply use smaller barrels—some only three or five gallons as opposed to the standard 53—that have a higher ratio of surface area to volume. New York’s Tuthilltown Distillery became the face of that strategy with its popular Hudson Baby Bourbon. Others steep their whiskey with a sack full of woodchips like a big oaky teabag (Copper Fox Distillery) or even chop up a barrel and let it infuse the whiskey in a pressurized tank (Cleveland Whiskey Co.)

The whiskey shelf at Butcher and the Boar

Sound is another strategy for manipulating oak. There’s research suggesting that ultrasound waves can cause plant tissues to rupture and release bioactive compounds (you may have heard of distillers putting subwoofers in their barrel rooms and treating their whiskey to hip-hop for hours on end.) Some bartenders mess around with the Sonicprep system—a sonic pulse-generating tool used by restaurants to create rapid infusions and stable emulsifications. If they add charred oak chips to a mixture of bourbon and vermouth, they can mimic a “barrel-aged” Manhattan in minutes.

The general problem with these oak-intensive methods is that the taste of aged spirits isn’t just the taste of oak. These polymers aren’t “extracted” from the oak tasting like fully matured bourbon. It’s time that degrades and recombines them with other compounds in the spirit to create a full range of nuanced flavor.

“All that does is speed up one end of the process at the expense of the other,” says Chris Montana, CEO and head distiller at Du Nord Craft Spirits. “I like rye whiskey, I love bourbon, but I don’t like the taste of barrels.”

That other part of the aging process—with all due apologies for short-changing the science in the name of brevity—is the process of esterification. Esters are those wonderful aromatics that happen when alcohol and acid have a chance to combine. “Say your fermentation yeast produced a tiny little bit of butyric acid, which tastes like puke,” explains Bryan Davis of Lost Spirits in Los Angeles (pictured, below.) “You combine that molecule with an ethanol molecule and you get ethyl butyrate, which tastes like a pineapple.”

Bryan Davis and the THEA One aging system at Lost Spirits // Photo courtesy of Lost Spirits

All of these compounds, from the wood and from the alcohol, spend years breaking apart and linking back up, to form those ineffable, complex flavors that give aged spirits their magic. And as you might imagine, distillers are searching for a way to speed up those reactions as well.

“Craft distilling is in its midlife crisis phase,” Davis jokes. “We’re tinkering, experimenting, and trying to figure out what works.” Davis has pioneered the most viable high-tech system to date that seeks to replicate both polymer degradation and esterification of spirits—and it began as a simple attempt to eliminate some guesswork.

“We set out to build a traditional distillery,” he explains. “It wasn’t intended to have this super cool and useful technology aspect for the actual production of spirits.” He wanted to engineer a technology that would help approximate how a certain barrel might taste over time. It grew into a reactor unit, of sorts, that accelerates each component of the aging process. His THEA One system (Targeted Hyper-Esterification Aging) uses heat to produce esters, UV light to break down polymers, and more heat to force more reactions between the two. His whiskeys have achieved cult status—selling out the moment they’re released.

The naysayers of rapid-aging have an easy retort to all this trickery—you can’t cheat time. The myriad chemical reactions are so many and so varied, that even if you’re able to replicate a few of them with more oak or pressure or light, you can’t replicate all the reactions that make up a storied Scotch or blue-ribbon bourbon. But craft distillers have a ready reply: we’re not trying to.

Photo via J. Carver Distillery on Facebook

“The root of it all is not about ‘acceleration,’ but about everything having to be the same,” says Bill Miller of J. Carver Distillery. “Why do small distillers have to play by industry standards? To me, that’s the opposite of craft and creativity.”

Consider craft whiskey’s competition. Companies like Beam Suntory (Knob Creek, Maker’s Mark) and Brown-Forman (Jack Daniel’s, Woodford Reserve) have conquered the economy of scale—generations of experience, thousands of barrels, and millions of dollars enable them to produce a long-aged whiskey for a decent price. That makes the local craft a tough sell—pay $15 more per bottle for a younger (and maybe less complex) spirit.

In that sense, the future of craft whiskey depends on creating products that consumers recognize as distinctly different from their go-to bourbon. It’s most certainly possible to create a delicious spirit in a couple years, or even sooner than that. The mistake would be to striving to make that spirit taste exactly like Maker’s Mark.

11 Wells has used smaller barrels to age their whiskey for less than one year.

“What smaller distillers have in their favor are in provenance and artistry,” says Michael Swanson of Far North Spirits. “Kentucky does what Kentucky does, for a host of reasons. There’s excellence for one location, but I don’t think ‘perfect’ exists. What we have to be out to prove is that we can make an excellent whiskey. I want my whiskey to taste like a Minnesota whiskey.”

Craft distillers have to find those new categories—to find new ways to make spirits that are both delicious and taste nothing like bourbon or Scotch. While the known universe of spirits contains some wonderful flavors, it’s inconceivable that it would currently contain them all. Perhaps those new flavors will come from distilling non-standard grains, or learning how to judiciously blend small-barreled whiskey, or from technologies yet to be developed.

The process of “rapid-aging” isn’t an attempt to cheat time, it’s just one of several ways to be different. It’s one small slice of an industry exploring every technique available in the hopes of landing on a new gold standard. We’ve all been conditioned to understand that bourbon and Scotch are the paragons of distilling perfection. But what if those are only the best we’ve been able to make so far? Miller poses a thought experiment that leaves me speechless—“What if Scotch isn’t good?”

About John Garland

John Garland is the Deputy Editor at the Growler Magazine. Find him on twitter (@johnpgarland) or in every coffee shop on West 7th Street.