Discovering the Innovations in Aging and Maturation of Bourbon

To create its acclaimed line of American whiskies, Jefferson Bourbons has used a range of experimental and pioneering aging techniques.


Innovation has been a hallmark of Jeffersons Bourbon from its very beginning.

When Trey Zoeller and his father founded the brand 23 years ago, they were focused on understanding how far they could push the boundaries of bourbon.

Zoeller first experimented with blending finished bourbons he bought from other distillers.

Nobody was blending bourbon at the time, he says. That was kind of the first realm of taking it outside of the traditional ways of maturing and bottling bourbon.

It wasnt until a decade or so later, while sharing a drink with a friend aboard an Ocearch shark tagging research vessel, that Zoeller realized that he could age the bourbon far outside of the traditional Kentucky warehouse.

I saw the bourbon sloshing around in my glass, he recalls, which led to an epiphany. Zoeller immediately began to wonder what would happen if one of his barrels of whiskey aged on the boat, which is what happened in the 1800s when the liquor was often shipped across bodies of water to major markets. So we started experimenting with that, he says.

Zoeller officially partnered with Ocearch and began his experiment by securing four barrels of bourbon aboard the ship, where the spirit would have ample opportunity to agitate during the five to 10 months it was out at sea. During the trip, the spirit would visit 30 ports and cross the equator a total of four times. What emerged at the end of that first trip was a hit in Zoellers mind and like nothing he had ever tasted before.

Those few months aging at sea were a revelation for Zoeller and Jeffersons Ocean officially launched in 2012. Now, the 21st batch of the special whiskey is currently aging aboard Ocearch. And given the huge number of variables, including weather conditions, no two of the editions have emerged exactly alike.

Theyre just the typical bourbon barrels, but when they get back theyre weathered, theyre beaten, they look like theyre 50-years-old, says Zoeller.

And the aging process is different. Some of the barrels lose a lot to evaporation, which really condenses the size of the yield. It makes it more briny because the salt air permeates the barrel.

Jeffersons Ocean now includes two additional bottlings, a cask strength bourbon and a wheated bourbonbut Zoellers curiosity in pushing boundaries didnt end with Ocearch. In fact, thanks to this wildly successful idea, Jeffersons has embraced experimentation and become known for its novel and highly innovative approaches to aging whiskey.

In 2016, Zoeller released two sets of Jeffersons Wood Experiments, which included five mini-bottles of cutting-edge whiskies. Each one began by filling a variety of different casks with mature bourbon that had already aged in new American oak barrels. This process allowed Zoeller to test out how different wood species and different toasting and charring techniques would affect the whiskey.

It also inspired Zoeller to develop a proprietary barrel with the Independent Stave Company that received an 18-month outdoor seasoning. Each cask was then given a grooved interior, flash-charred and toasted prior to being filled with Jeffersons Reserve Bourbon. After four months, the result was Jeffersons Reserve Twin Oak.

Why not incorporate all these other techniques that have been developed for barrels outside of the bourbon category? says Zoeller, whos now completed more than 200 experiments with barrel finishes. Its a learning process.

That philosophy led to the creation of Jeffersons Reserve Old Rum Cask Finish, the result of a partnership with friend and colleague Malcolm Gosling, Jr. of Goslings Rum. Zoeller has also finished his bourbon in casks that previously held different kinds of wines made with Cabernet Sauvignon grapes. The wines aged in these barrels are big and bold, coming from Groth and Pritchard Hill in Californias Napa Valley.

To his delight, each one turned out dramatically different, picking up each wines unique terroir.

The one from Groth grows on the Valley floor and the one from Pritchard Hill is known as a Mountain Cabits grown between a 1,000 to 2,000 feet above sea level on the side of the hill, which really stresses out the vines and brings more sugar into the grapes, says Zoeller. In this case it gives it a black cherry and chocolate flavor, and that comes out into our bourbon. Even though these wineries are less than five miles apart from the way the crow flies, they taste a world apart because of that difference in elevation.

The difference in flavor prompted him to try this out with two more wineries, this time partnering with Chteau Pichon Baron and Chteau Suduiraut in Bordeaux, France. These finishes, he says, displayed a very different kind of earthiness than those of the Napa Cabernets.

Zoellers experiments have not only proven a success for Jeffersons, but theyve also been eye opening for other bourbon lovers. Hes even caused some of his contemporaries to raise an eyebrow or two.

I dont think theres any question that theres always going to be the traditionalist that only wants bourbon distilled one way, says Zoeller. What I say is Baskin-Robbins had 31 flavors for a reason.

Please sip responsibly

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