Barrel-Aged Beer

Recently, Dangerous Man Brewing Company was offered the opportunity to barrel-age their Imperial Chocolate Milk Stout in a Wild Turkey Bourbon Barrel. This beer was presented in the VIP tent of the Winter Beer Dabbler and made a definite impression. We thought we’d give you some background to barrel-aged beer, some history, some process, and in all honesty, some longing to a beer poured and gone.

Before the use of stainless steel tanks, most modern fermentations wine and beer took place in/on wood. When wet, wood expands and creates a water-tight seal making it the go to product for transporting or holding wet goods. Coopers, masters of barrel-making, cut the wood into staves of particular size and length, use heat to bend the staves, bind them with wooden or metal hoops, and fill them with water so that the wood expands to create a seal.  Barrels were very useful for holding a variety of goods in a world before pallets, shrink wrap, and complex metallurgy.

For the most part, the barrel world was reserved for spirits and fermenting wine, while much of the beer world was using large foedres to ferment and wooden firkins or casks to distribute and carbonate. Because of the short carbonation times on the beers in the casks and firkins, they are and were consumed quite quickly, lending slight wood flavors to the beer and most likely just increasing the thickness of the beer’s draw. Much of the strong wood flavors that we often associate with wines, such as oaked chardonnay, were not present in the beer world as carbonation was hard to hold, and I don’t think there’s a person in the world who enjoys flat beer.

Barrel-aging seems to be a relatively new trend in the beer world, as stronger stouts, porters, and barley wines find pleasant aging and oxidation when sitting on barrels. Barrel aging helps to lend tannins and vanillins to beers, both drying them out and adding distinctive vanilla tones. Because each barrel is charred on the inside, to sanitize the barrel and insure a huge amount of the liquid inside isn’t soaked into the wood, there are often elements of toasted wood imparted into the beers. Large alcohol beers are put into barrels as over time alcohol and water evaporate out of the barrel in process dubbed, “the angel’s share.” Through time and evaporation, beers that started out with large alcohol contents and are quite hot to consume, mellow out, become softer, more-rounded, and become more complex in flavor.

Virgin barrels are rarely used in the beer world, as they are more expensive and tend to give too much “woody” flavors. Instead, whiskey, wine, and other spirit barrels, are re-purposed as beer aging barrels. This creates unique taste blends of the original beer, the unique flavor of the woods itself, and remnants of whatever liquid was previously held in the barrel. If you search in the beer world today, you’ll find beer aged on whiskey, port, wine, tequila, Tabasco, brandy, and any other sort barrel that has held spirit to age on. Beer is made for the barrel, so different styles of beer are now being made dependent on what kind of barrel the brewery has purchased. You’ll often find sours in wine barrels, stouts in whiskey and brandy barrels, belgians in liqueur barrels, and weird amalgamations in just about everything else.

Often barrels are used for several years before they become inoculated with wild yeasts and bacteria, such as brettanomyces and lactobacillus. Once a barrel is infected there is nothing you can do to remove these somewhat problem yeasts. Instead, brewers can purposefully sour and funk their beer by aging them in these barrels and allowing the bacteria and yeast to consumer whatever leftover sugars are left in the beer. The bacteria and yeast can consume sugars typical beer yeast can’t, allowing beers to gain more alcohol content, become drying, and gain a flavor complexity that can’t be found when fermenting with a typical brewer’s yeast. Sour programs are starting up all over the country, and have become one of the more popular styles in the beer world.

Dangerous Man’s Imperial Chocolate Milk Stout (ICMS) aged on Wild Turkey oak barrel, was fanatastic! The large chocolate additions in the ICMS became balanced by the rich vanilla and bourbon flavors imparted by the wood and whiskey, respectively. Further additions of cocao nibs were added to the barrel to round out the original chocolate flavor. Due to the angel’s share and the natural oxidative nature of wood, the beer gained a rounder, fuller draw than it’s original style and mellowed out the heat of the huge ABV beer. This was a very limited run beer, and we’re sad to have seen it gone, but we hoped to give you an idea of what it was all about. Included below are some pictures of us filling and maintaining this barrel, with fingers crossed, hopefully we’ll see another one soon!

Check out some pictures of Keigan and John preparing the barrel below!

Keigan flushing and filling the barrel with water to ensure that it seals.

Keigan flushing and filling the barrel with water to ensure that it seals.

Keigan and John adding cacao nibs to the barrel for further chocolate flavor.

Keigan and John adding cacao nibs to the barrel for further chocolate flavor.

Keigan hammering the bung into place.

Keigan pounding on that bung.

The barrel carbonating. This purges out any leftover oxygen in the barrel.

The barrel carbonating. This purges out any leftover oxygen in the barrel.

The barrels resting place; tucked quietly away with the firkins.

The barrel’s resting place; tucked quietly away with the firkins.