In brewing, BBL is the notation for “barrel,” a unit of measurement equal to 31 gallons. This is not to be confused with an oak barrel, which typically holds nearly two BBLs of beer. Still with us? Great. Blue BBLs, then, is a special blend of our bourbon barrel-aged imperial stout with our bourbon barrel-aged sour stout, plus an addition of juicy blueberries, which impart vinous tones. The acidity from the sour stout seamlessly balances the sweet malt character of the imperial stout, and the tannins from the berries amplify the fruity character, altogether exhibiting notes of red wine, blueberry skins, rich toffee, roast and singed oak.