Today’s beer brewers realize that much can be gained by aging their beers in barrels that once held other fermented beverages. They also realize that barrel aging isn’t an exact science; in fact, it’s much closer to an art form. And many brewers are learning as they go.
Barrel-aging beer isn’t simply a matter of brewing a beer, fermenting it, letting it sit in a barrel for a few weeks or months, and then packaging it. A handful of variables come into play when barrel-aging beer. When it comes to choosing barrels for their beer, brewers have to consider the following:
What kind of barrel will be used (wine, cognac, whiskey, and so on)?
What’s the base beer style (Porter, Stout, Barleywine, and so on)?
Will the finished beer be straight (unblended) or blended with another beer?
Types of barrels for aging beer
Brewers have the following barrel choices for barrel aging:
Bourbon barrels: Right now, American bourbon barrels are the hottest ticket for barrel aging. One reason is their easy availability. Another reason is their intense flavor characteristics.
By law, bourbon must be aged for two years in new American oak barrels, and the barrels can be used only once, which means bourbon distillers must rid themselves of thousands of almost-new casks every year. Soaked with the potent flavor of bourbon, these barrels have new roles to play in the aging of rum, tequila, sherry, and now beer.
Bourbon barrels are charred on the inside, according to the distiller’s specifications; they can be lightly charred or they can be heavily charred. This char, along with the oak character, can permeate the beer, creating an incredible blend of vanilla, caramel, toffee, toast, and/or smoke aromas and flavors.
Wine and sherry barrels: Wine and sherry barrels (and to a lesser extent, cognac barrels) are also used with great success. Chardonnay wine barrels, for instance, which aren’t charred, infuse the beer with warm oak toastiness and coconut and vanilla aromas and flavors.
Whiskey barrels: Whiskey barrels give beer flavors similar to those gained by aging beer in bourbon barrels, but whiskey barrels aren’t as plentiful.
Choosing an old barrel flavor for aging beer
In this new age of beer enlightenment, brewers who are making that foray into barrel-aged beer are discovering that a lot of choices exist when it comes to choosing what type of barrel to use to age their beer. Each barrel has its own personality and character and presents a different possibility.
Choosing between wine and whiskey barrels isn’t always a simple choice, but choosing between different types of wines (red or white), fortified wines (port and Madeira), and distilled wines (brandy and cognac) makes the decision even harder. The choices also extend beyond bourbon to other distilled spirits, such as scotch, rum, and tequila.
Generally speaking, bourbon and whiskey barrels are perfect for dark and rich beers, like Imperial Stout, because the dark grain flavors of the beer meld wonderfully with the charred, smoky character of the wood. Wine barrels are for more delicate flavoring. Paler beer styles, such as India Pale Ale, may work better with wine barrels that lend their fruity character to the beer without imbuing any smokiness or color.
Whenever sherry or cognac barrels are used to age beer, it’s usually at the whims of the brewer. No hard, fast rules exist about mixing and matching beer styles and barrel types in the brewhouse.
Much of what’s taking place in the craft-brewing industry these days as it pertains to aging beer in and on wood is completely experimental. To what extent a brewer can foresee the outcome of any beer that’s aged long-term in a wooden barrel is questionable — especially those brews that are blended. Only repeated experimentation yields predictable results.