Any style of beer additionally aged in a wooden barrel that previously contained alcoholic beverages. As a result of aging, the beer acquires additional softness, roundness, depth of taste and complexity of the bouquet. This method of making beer is rarely used on an industrial scale, it is more typical for craft brewing. The barrel can be made from oak or another type of wood. It is possible to use containers from wine, bourbon, whiskey and other types of alcohol.
A mandatory style requirement is the clear notes of alcohol previously contained in the barrel. In addition, oak (or other wood) tones should be felt in the beer, nuances of vanilla, caramel, toast, bread, nuts often appear. It is important that all profiles are balanced, the additional alcohol character is not scalding. Slight oxidation is possible, but no one flavor should dominate over the others. The underlying style should be easily recognizable.
During aging, the beer becomes darker, stronger, and astringency appears. Slight background acidity is acceptable. Most often, a full-bodied dense beer is taken as the basis.
Density, bitterness, color, strength and other characteristics depend on the base, but usually strength and density increase during aging.
