Barrel-aged beers are so trendy that nearly every taphouse and beer store has a section of them. It may be fashionable, but brewers are capitalizing on what vintners and distillers already know: wood aging can mellow some harsh edges as well as add structure and complexity. A barrel brings three components together to transform a beer. The first is whatever was in the barrel before, such as bourbon, rum, or wine. The oaken staves soak up flavors that diffuse into the beer. The second element is the wood itself. Woodiness, tannins, and vanilla are most common, but you can often taste coconut and caramel notes as well. The final factor is oxygen, because barrels breathe. The wood allows for a slow injection of oxygen that ideally skews the flavors toward sherry, toffee, and nuts.
Commercial brewers aren’t the only ones taking advantage. Homebrew clubs may chip in on a barrel and blend a dozen or so 5-gallon (18.9 l) batches to fill it. It’s also relatively easy to find smaller, individually sized barrels, although they’re not cheap. In either case, adding a barrel to your home brewery is not so simple. Above and beyond the starting costs and possible wait list, maintenance and storage require a fair amount of effort. Over time, bacterial infection can also become an issue, which is not so pleasant for that imperial stout you wanted to age.
But let’s say you’re not ready to drop $150 to speculate on a 5-gallon (18.9 l) barrel or you don’t want to worry about keeping one clean and operational. You can still capture some of that barrel magic in your own beer bottles by using oak in your fermentor or keg. You won’t get the oxidation piece, but your beer will still benefit from the other aspects of wood aging.