In the past, beer was fermented in wood, matured in wood, transported in wood, and stored in wood. There was a lack of better materials available for most of history, so wooden casks and beer went hand-in-hand for centuries. These days, wooden casks mainly are used to impart certain flavours into beer that can't otherwise be attained through other brewing practices or ingredients. One of the most common barrels that beer is matured in is bourbon barrels. This is partly because bourbon barrels are in good supply as bourbon in America by law needs to be aged in new charred oak. After the whiskey has been transferred out of the barrel the distiller can sell the barrel off to be used for another purpose. Surely, another reason for the prevalence of bourbon barrels in beer maturation is flavour. Barrels that have previously held bourbon often infuse flavours of caramel, maple, brown sugar, vanilla and toffee into beer. Experimentation in barrel-aging beer is commonplace today and almost any style of beer you can imagine has been barrel-aged in some manner. Types of barrels used in brewing include but aren’t limited to: red wine, scotch, rum, brandy, and even occasionally white wine, and gin.
A blend of aged and un-aged imperial saisons, matured in red wine barrels. The result is a golden beer that is pleasantly tart and lightly funky. Bright aromas of tropical fruit and white grape are met with flavours of lychee, stone-fruit, and a bit of barnyard funk.
This Russian imperial stout is matured for nearly a whole year in Kentucky bourbon barrels. This beer boasts massive flavours of vanilla bean, dark cherries, and bittersweet chocolate.