Maker’s Mark has unveiled a new limited-release bourbon, and for the first time consumers won’t have to travel all the way to Kentucky to pick up a bottle. The first installment of Maker’s Mark Wood Finishing Series—a release known simply as Release: RC6 (more on the name later)—marks the first nationally available limited-edition bourbon from the iconic distiller and will hit store shelves nationwide over the next couple of months.
That’s no small development for a distillery that has added exactly one new whiskey (Maker’s 46) to its core lineup in more than six decades of making its signature wheated bourbon and has historically released only a small number of experimental, limited-release bottles for purchase at its distillery in Loretto, Ky. It’s a move that signals not only a new chapter for Maker’s but also the direction of the larger bourbon industry. Consumers want more and different whiskeys, prompting even the most traditional distillers to innovate.

At Maker’s, that means a whole lot of experimentation in wood finishes for its flagship bourbon, which typically spends five to six years in American oak casks before bottling. Maker’s 46—released in 2010—represents the first commercial outgrowth of Maker’s experimental wood finishing efforts. By taking cask strength Maker’s and inserting 10 specially seasoned French oak wood staves into the cask for the final nine weeks of aging, Maker’s produced a bourbon emphasizing notes of vanilla, caramel, and spice. The distillery’s Private Select program, which allows customers (mainly bars and restaurants) to craft their own unique barrel of Maker’s by selecting from a menu of finishing staves, grew out of that original experimentation.
Those forays into wood finishing experimentation have not only continued behind the scenes for the past decade but also accelerated. “This product is 65 years old, made by traditional practices passed down through the decades,” says Jane Bowie, Maker’s Mark director of Private Select. “And it’s only now that we’re figuring out the science behind those practices. It’s not like they were talking about ‘lignan degradation’ back then.”
They’re certainly talking about it now. Working with partners at nearby Independent Stave Company (ISC), a maker of barrels for the wine and spirits industries, Maker’s has in recent years poured ample time and resources into defining and developing wood staves that can impart or amplify very specific flavors to its bourbon.

It’s a highly scientific approach to what is largely considered the art of distilling and maturing bourbon. Working with ISC’s Research Center (that’s the “RC” in “RC6”), Bowie and her team have tested and tasted hundreds of such experiments, as ISC’s researchers have subtly tweaked the aging, toasting, and treatment of various wood staves. The resulting tasting notes have ranged from mocha and tobacco to “baby vomit,” Bowie says.
For the bourbon now released as RC6—“6” being the sixth stave recipe the ISC Research Center developed at Maker’s direction—Bowie and her team wanted to preserve the fruity notes abundant in the yeast Maker’s uses in distillation. “Our yeast tastes like hefeweizen,” Bowie says. “So we started talking about those fruit characteristics that are so prominent [in the yeast] and that are often underappreciated, because of the caramel and the vanilla and all those classic wood notes you get. Sometimes the yeast and the distilling gets lost in the product.”
The American oak finishing staves developed for the RC6 release first spent 18 months outdoors, exposed to the weather on a lot outside Independent Stave’s cooperage in Lebanon, Ky. This “seasoning” process allows the wood to dry and break down somewhat (that’s your “lignan degradation”), leaching out bitter tannins and preparing the staves to better interact with the liquid (for comparison, most staves spend three to six months seasoning before being crafted into barrels). ISC then toasted them in a convection oven—the exact time and temperature is a trade secret—before Maker’s inserted them into barrels of cask strength Maker’s Mark for exactly eight weeks and five days.

This specific process took two years of experimentation to perfect, Bowie says, but the results speak for themselves. The sought-after notes of ripe fruit come through on both the nose and palate along with additional notes of baking spice layered atop Maker’s traditional vanilla and caramel flavors. RC6 is distinctively Maker’s, but the fruit on the nose and the brightness on the finish make for a unique spirit and—along with the baking spice—an autumnal bottling that could hardly be more appropriate for a late-September release. Just 255 barrels were produced (so between 45,000 and 50,000 bottles, roughly), but at a suggested retail price of $60 you’d hardly know it’s a limited release.
Maker’s plans to release a new iteration of its Wood Finishing Series annually, and Bowie and company are already hard at work on their next round of experimentation, a process that never really stops. “We spend so much of our time trying to understand why things taste the way they do,” she says. “So this is just a way to share that with the public.”
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