There was a time not so long ago when happy hour consisted of knocking back a few pints or maybe a G&T. But as cocktail culture continues to grow more ambitious (and classics like martinis become old hat), bartenders are once again upping the ante. The next big thing: barrel aging premixed cocktails behind the bar, including the one you have at home.
The trend can be traced to a London watering hole called 69 Colebrooke Row, where bartender Tony Conigliaro began bottle aging manhattans in the early 2000s. Its popularity in North America is largely attributed to Jeffrey Morgenthaler, bar manager at Clyde Common in Portland, Ore., and author with Martha Holmberg of this year's The Bar Book: Elements of Cocktail Technique, who saw what Conigliaro was doing and took it one step further in 2010 by aging his manhattans, negronis and tridents (made with aquavit) in wooden casks. The result in both cases was milder, mellower drinks with earthier, fragrant notes.
As counterintuitive as barrel aging cocktails may seem – mixed drinks, after all, are made using spirits that are already aged – Matt Jones, the Canadian whisky ambassador for Beam Suntory, which makes Jim Beam and Knob Creek, calls it a logical next step in the field of mixology. "If you look back at the evolution of spirits starting from the 1830s, there is a progression to experimenting with different casks and aging times," he says. "It's a classic case of what's old being new again."
Morgenthaler cites a vintage 1910 ad from American alcohol company Hueblein Inc. promoting pre-mixed and wood-aged cocktails as the first evidence of this sort of tinkering. Before that, Jones points out, cask aging can be credited with giving rise to some of the world's most beloved spirits.
Among them is bourbon, for which wood barrels became the most practical storage receptacles because the only other options were glass masonry containers, an obvious disadvantage when it came to transporting it. As bourbon made its way down the Mississippi, the constant sloshing of the liquid inside the barrels (as well as the exposure to extreme temperatures and direct sunlight) informed the spirit and intensified its flavours.
According to Jones, who's a specialist in it, bourbon is the ideal spirit to use in a cask-aged cocktail since it's a raw distillate, meaning that it's strong and stands up well to aging. "Barrel aging mellows a strong spirit like bourbon and enhances its underlying flavour notes, such as vanilla, caramel and toffee," he says. The process, moreover, can easily be pulled off at home, says Jones, who calls it no harder than shaking and stirring. "A good way to start off is to make a batch of your cocktail of choice and put it in a mason jar with a barrel stave. That way you can see what changes in the cocktail without running the risk of ruining a large batch of alcohol in a whole barrel."
When you're ready to try it with an actual barrel, proceed, Jones says, with a fairly simple cocktail, like a manhattan or an old-fashioned, filling the barrel with water and letting it sit overnight to allow the wood staves to swell (this ensures it won't leak). Next, mix your cocktail and pour it into the barrel (avoid fresh ingredients such as milk, eggs, fruit or cream, which will spoil during the aging process), then store it in a cool, dry, dark place. If speed is of the essence, leave it in a spot where it will be exposed to sunlight, which will hasten the aging process and give the cocktail a more intense flavour.
For a one– or two-litre barrel, 10 to 14 days of aging will suffice, Jones says. (Larger barrels will require longer aging periods; see recipe at left.) But start tasting the cocktail as early as seven days in. "You have to keep a close eye on it as one or two days too long in the barrel could ruin your cocktail," he says.
Although barrels both new and used can be purchased online, Oliver Stern, owner and bartender at the Toronto Temperance Society, recommends getting the most out of a new one. "You can season a barrel with bourbon first by filling it and then letting [the liquor] steep for a month or so," he says. "But you might as well get the full potential of the wood in the first go. The oak from the barrel is what adds roundness to your cocktail."
At his bar, Stern is used to custom-tailoring drink orders for clients; when it comes to home entertaining, though, he likes the idea of serving cask-aged cocktails because it adds an exclusive dimension to parties – not to mention the fact that it frees up the host from working behind the bar all night.
"The tricky thing about entertaining is that I'm always mixing cocktails and don't have a chance to relax and enjoy myself," he says. "But if I have a cocktail ready to go, I'm not stuck making drinks all night."
Jones calls the practice "unique and boutique-y." If all goes well, your guests will also be calling the results delicious.
Barrel-Aged Manhattans (party edition)
The following recipe from Jeffrey Morgenthaler (www.jeffreymorgenthaler.com) makes three gallons
256 oz (approximately 10 750-ml bottles) rye whisky
128 oz (approximately five 750-ml bottles) sweet vermouth
7 oz Angostura bitters
Stir ingredients together (without ice) and pour into a three-gallon oak barrel. Let rest for five to seven weeks and pour into glass bottles until ready to serve.