Two of Cincinnati's most recognizable names in alcohol have done something that makes a lot of sense when you think about it — they've made a whiskey together. Rhinegeist Brewery and New Riff Distilling have officially released DUET, a collaborative American whiskey that draws on the deep connection between brewing and distilling, and the result is something that doesn't quite fit into any familiar box.
A Natural Partnership Built on Shared Roots
The collaboration between the two companies wasn't born out of a marketing meeting or a business strategy session. It grew out of years of friendship between the teams on both sides of the Ohio River. New Riff is based in Newport, Kentucky, just across from Cincinnati, where Rhinegeist has been operating out of the Over-the-Rhine neighborhood since 2013. The two companies have traveled in the same circles for years, and that familiarity is what made this project possible.
The concept behind DUET is rooted in one ingredient that both brewers and distillers rely on heavily: barley. It's the backbone of beer styles like stouts and porters, and it plays a central role in certain categories of American whiskey as well. That common ground gave the two teams a natural starting point, and they built the entire whiskey around it.
New Riff master distiller Brian Sprance put it plainly: "This collaboration wasn't intended to recreate something that already exists. Brewers work with an incredible range of grains, malts and yeast strains, and with our shared background in brewing, that creative overlap between us and Rhinegeist felt very natural. The result is a whiskey that's a little unexpected for Kentucky, and a great reflection of what can happen when distillers and brewers who've known each other for years come together to create something new."
That last part — "a little unexpected for Kentucky" — is worth sitting with for a moment. Kentucky bourbon has a clearly defined identity. It's corn-heavy, straightforward in its grain composition, and deeply traditional. What Rhinegeist and New Riff put together with DUET is something that bends those expectations without breaking them.
The Mashbill and Aging Process
The grain bill for DUET is one of the first things that separates it from most American whiskeys on the shelf. The mashbill is made up of 57% malted barley, 37% raw barley, and just 6% rye. Together, barley accounts for 94% of the entire recipe. That's an unusually grain-forward approach by any standard, and it reflects the brewing influence that Rhinegeist brought to the table.
Most bourbons are required by law to be at least 51% corn. DUET is not a bourbon — it's classified as an American whiskey, which gives the producers more flexibility with their grain composition. That flexibility is exactly what allowed them to push the barley percentage this high and create something that genuinely bridges the gap between a malt-heavy craft beer and a well-aged spirit.
The aging process is equally unconventional. The majority of DUET was matured in new American oak barrels, which is standard practice in American whiskey production. But a portion was also aged in Spanish oloroso and Pedro Ximenez sherry casks — two varieties known for adding rich fruit character and a distinctive sweetness to whatever they touch. Sherry cask maturation is far more common in Scotch whisky production than in American whiskey, which adds another layer of unexpectedness to what's in the bottle.
What makes the aging process truly unusual, though, is what happened after the barrel aging. The blended whiskey was transferred into a large foeder — an oversized wooden vessel traditionally used in Belgium and Germany for fermenting and aging beer — located in the basement of Rhinegeist's facility. That foeder had been used for beer maturation, meaning it carried flavor compounds from previous batches when the whiskey moved in. After spending time in the foeder, the whiskey was then re-barreled into used American oak to finish the process and allow the various elements to settle into a cohesive whole.
Sprance described the creative process with the kind of honesty that makes the whole project feel real: "The best part of this was collaborating with Luke Cole and the whole Rhinegeist team forever. We've known them forever. They're all very dear friends. We knew we use a good amount of malted barley for our whiskey, and we knew we really wanted to incorporate the foeders down in their basement. There's not a lot of examples of this kind of stuff out there, so we were just making it up on the fly … It was kinda just putting our peanut butter in their fudge and seeing what we could do."
What's in the Glass
DUET has been aged for a minimum of six years and is bottled at 111.2 proof — a high proof point that puts it in the same territory as cask-strength and barrel-proof releases that have become increasingly popular among serious whiskey drinkers. At that proof, the whiskey delivers a lot of flavor without being inaccessible, particularly for those who enjoy adding a few drops of water to open things up.
On the palate, the whiskey leads with sherry and tangerine — a direct result of the sherry cask influence during maturation. Those fruit-forward notes are layered over a savory, grainy foundation that comes naturally from such a barley-heavy grain bill. There's also a spicy element that runs through it, likely amplified by the high proof and the rye component, even though rye makes up only a small fraction of the mashbill.
The result is a whiskey that pulls in several directions at once and somehow holds together. The sherry sweetness and citrus brightness from the cask work give it a softness that you might not expect from a 111-proof bottle. The barley gives it an earthiness and savory depth that reminds you this is something made by people with a serious background in grain. And the foeder aging adds a subtle complexity that's genuinely hard to place — which is part of the point.
The Label Has a Story Too
The bottle itself is worth mentioning, because the collaborative spirit that went into the liquid extends to the packaging as well. The label was designed by Jared Wagner and Chloe Rethman, graphic designers for New Riff and Rhinegeist, respectively. The two met while both were working at FC Cincinnati, the city's Major League Soccer club, and were married in May of last year. Designing the DUET label together was, in a sense, its own kind of collaboration — one that mirrors the partnership between the two companies in a personal and somewhat poetic way.
It's the kind of detail that could easily be overlooked, but it adds something to the product. DUET isn't just a co-branded release thrown together for a limited run. It's the product of relationships that developed over time — professional, creative, and personal — between people who genuinely know each other.
What It Means for the Region
Cincinnati has a strong brewing identity. Rhinegeist, named after the German phrase meaning "ghost of the Rhine," operates out of a historic 19th-century brewery in a neighborhood whose entire character was shaped by German immigrant brewing culture. That heritage runs deep in the city, and Rhinegeist has done a lot to keep it relevant for a new generation of drinkers.
New Riff, for its part, has built a reputation as one of the more thoughtful craft distilleries in Kentucky — a state with no shortage of competition. New Riff has long used a higher-than-average malted rye content and has been willing to experiment in ways that larger Kentucky producers typically avoid.
Rhinegeist CEO Adam Bankovich addressed the regional significance in a statement: "We're thrilled to add another layer of meaning to Spirit of the Rhine, Rhinegeist's eponym, when limited quantities of DUET are released across Ohio and Kentucky in concert with our friends across the river at New Riff Distilling. The project was inspired by the mutual appreciation our teams have for each other, and it is no surprise the past year of collaboration has been so harmonious."
The phrase "Spirit of the Rhine" carries a double meaning here — a nod to Rhinegeist's name and history, and a literal reference to the spirit being produced. That kind of connection between heritage and the liquid in the bottle is what makes collaborations like this one resonate beyond the novelty of two brands working together.
Where to Find It
DUET American Whiskey is currently available at New Riff's gift shop in Newport, Kentucky, and at select retailers across Ohio and Kentucky. It's also available by the pour at The Aquifer Tasting Room at New Riff and at Rhinegeist's Tap Room in Cincinnati. Availability is described as limited, so those interested in tracking down a bottle would be wise to act sooner rather than later.
For collectors and enthusiasts who pay attention to this part of the American whiskey landscape, DUET represents something more than a seasonal release or a marketing exercise. It's a serious, thoughtfully constructed whiskey that came out of a genuine creative process between two operations that have earned credibility in their respective fields. The fact that it's a little unusual — the barley-forward grain bill, the sherry casks, the foeder aging — is exactly what makes it worth seeking out.
American whiskey is in a period of genuine experimentation right now, with producers across the country pushing against the traditional definitions of the category. DUET fits squarely into that movement, but it has something a lot of experimental releases lack: a clear sense of place. It's a Cincinnati whiskey, in every sense of the word.
