Let’s talk about an interesting topic: Barrel-aged beers. I started thinking hard about these after I just paid $9.99 for a 16oz bottle of Bourbon County Stout this Black Friday. It got me thinking: I’m a competent homebrewer, I’ll just crank out a batch and age it myself. Experience making high gravity beers: Check. Tasty RIS recipe: Check. Barrel-aging: Um, not so much. And there lies the sticky point: Barrel aging. It’s something home brewers struggle to replicate short of getting together with a club, buying a barrel, and brewing 55-60 gal to fill said barrel. I personally have little to no experience with it. I’ve oaked a few beers before, but none had anything close to what I would call “barrel-aged” flavor.
So I’ve spent the last weeks putting a few things together. First, a recipe for a 12-13% ABV Imperial Stout that will serve as the base beer for many adjunct-filled adventures over the next few years. Second, a plan for starting a home-brewed vertical of my own, including some sweet labels. The plan is to brew a barrel-aged stout once a year, then age it for a full year. Each year’s batch will get a different adjunct (vanilla bean, coffee, chocolate, etc). Next, I went ahead and brewed that recipe for the massive Imperial stout over the weekend. It’s fermenting away happily (read:vigorously) right now. Lastly, and most importantly, I’ve spend a lot of time thinking about just how the hell can we recreate barrel aging at the home brew scale.
Let’s first talk about what the status quo seems to be for replicating bourbon barrel-aged flavor at home. Buy some toasted oak cubes, toss them in some bourbon for awhile, then add them to the beer for another length of time. There’s a few variations to this method, but most seem to follow that script. The issue is, it just doesn’t re-create that barrel aged flavor commercial examples have. Also, we end up having to add large amounts of bourbon (4-12oz) to get a noticeable effect. That is order of magnitude more than a barrel-aged beer picks up from the barrel. There’s got to be another way to do this. Used barrels are expensive and just too big. New 5-gallon ones are available, but new barrels present their own problems.
The issue of oxidation, or lack of, is something that many advanced homebrewers have made some headway on. From using oak dowels, to aging in plastic buckets, there seems to be a few clever methods to slowly allow O2 into a beer while aging. I’d actually like to hear if anyone has experience with these methods. I’m not going to focus too much on the oxidation topic today. As of right now, I’m planning to vent the headspace of the keg (pulling the release valve for a second) once or twice while the beer ages.
The issue of replicating that bourbon barrel flavor is what I’d really like to talk about.. I’ve literally spent the past couple weeks thinking long and hard about what we’re missing at the home-brew scale. I’ve scoured the internet as well, but didn’t find much. I know batch sizes and surface area make a difference, but they can’t have that much of a difference. So why is it that real barrels create the effect we’re looking for, but oak cubes and bourbon can’t?
Finally a eureka moment hit. I’ve seen videos showing how whiskey barrels are made. They’re charred black like charcoal on the inside under intense flames. The oak cubes we use for brewing are merely toasted. Could that be the difference? Well toasted oak cubes were designed to replicate wine barrels, as the wine industry uses toasted oak barrels rather than charred ones. So I did some searching to see if anyone was talking about using charred oak in beer, and there doesn’t seem to be anything meaningful. I finally stumbled across a four year old post post on HBT where KingBrianI tested the differences between toasted oak and charred oak in moonshine. Now feeling like I was onto something, I thought maybe the home distillers have thought of this. I searched “distilling oak char”, and BOOM. Turns out our brothers on the illegal-side of the fence have done quite a bit of research on the topic. They face the same dilemma we do, in that toasted cubes seem to be the only product readily available on the market short of buying a new barrel. So many of them char their own oak using MAPP, propane, or oxy-acetylene torches. There’s a very detailed post on the artisan distiller forum experimenting with just this topic. The person found the charred examples had more ‘bourbony’ character to un-aged whiskey than toasted oak did. Maybe the answer is right in front of us; we’re using the wrong oak.
So what’s my plan? Well I’m not entirely sure, as I don’t have experience with any of this. Anything I try is just going to be a shot in the dark. I do feel like I’m onto something here though, so shoot in the dark I will. As for right now, I’ve got a giant Imperial Stout (1.118) cranking away in the primary. I’ll post some recipe details here in about 2 weeks once it’s ready to go down for a year long-nap in the keg.
I purchased some medium-plus toast American Oak cubes. Why toasted? It seems most cooperages toast the inside of the barrels prior to charring to bring out more of the vanillans. Next I’m going to blast the cubes with my propane torch until they’re charred. I have zero experience charring oak cubes, so I’m just going to guess how much is enough. There’s quite a few photos of bourbon barrels indicating their level of char. I’ll try my best to replicate that.
The charred oak cubes should be pretty similar to buying a new 5 gallon barrel. The charred oak is going to impart entirely too much flavor into the beer in a very short period of time. After all, we’re trying to replicate a barrel that held whiskey for over a decade. The charred oak loses a lot of it’s ‘essence’ over the years, as the whiskey gets darker and more oaky. So my plan is to soak the charred cubes in un-aged whiskey for at least a month, and then possibly some bourbon for another month. Hopefully that will help leech a good amount of the flavor from the cubes. Will two months of aging the cubes replicate the ten years or more of a traditional barrel? No clue, but there’s only one way to find out.
So that’s about it for now. There will be more posts to follow on this soon. I’m extremely curious if anyone has experience using charred oak in beer. I’ve searched extensively, but that doesn’t mean there isn’t someone out there. Not everything finds it’s way onto the internet =) Also, if anyone has any experience on the oxidation front, I’d love to hear from you as well.