In 2006, Kuhnhenn Brewing Co. out of Warren, Mich. released a version of its olde ale, Fourth Dementia, that had been aged in bourbon barrels for nine months before being bottled. The final beer, named Bourbon Barrel 4th Dementia, comes in at a whopping 13.5 percent ABV and is sold exclusively in 12-ounce bottles.
The first release of the beer was quite small, but as more and more people tried it and loved it, Kuhnhenn began brewing—and barrel aging—more and more of it. Fast forward to Dec. 21, 2012, when Kuhnhenn held its annual Winter solstice event, where it sold bottles of the olde ale for $7 each, with a 12 bottle per person limit.
The Kuhnhenn Brewing Co. website has a bit more information on the beer:
Our version of a classic English Olde Ale takes the style to new depths of flavor intensity. After several months conditioning, 4D is transferred into Bourbon barrels for several more months before being released. This ale has an intense, sweet caramel malt flavor and aroma that quickly develops into notes of toffee and toasted marshmallows. The barrel aging adds a slight whiskey character, complemented by subtle notes of vanilla sweetness. As this beer ages, alcohol flavors will fade away and round out, bringing out a mild sherry note with a long, lingering finish.
The Kuhnhenn Bourbon Barrel 4th Dementia pours a muddy reddish burgundy with very little head, although there is a tiny amount of off-white lacing left behind. Aroma from the glass is a combination of butterscotch, sweet vanilla bean, creamy oak, dark chocolate, carmel, malt and greens.
From the start, the Bourbon Barrel 4th Dementia is quite sweet on the palate, with marshmallows and caramel making up the dominant flavors, while toffee, vanilla beans, oak and yeast come in close behind. There is very little carbonation—which is not unexpected with this style of beer with this high of an ABV—but the mouthfeel is very full-bodied, almost syrupy on the palate. The alcohol is extremely well hidden, although it does become evident on the finish, especially as the beer warms up. In addition, I taste a interesting tarty fruit note that reminds me strongly of plums combined with oak on the finish, both of which increase in strength after it is been in the glass for a few minutes.