For more about this brewery’s approach to big, barrel-aged imperial stouts, see Brewing and Blending Leviathans with Bluewood.
Bluewood was born out of the idea that everything would touch oak or have some special process involved. I started this with Grant Lodholz—both of us engineers—and we work backwards, creating the beers in terms of their intensity. That complexity was really what interested us. We’re constantly trying to entertain ourselves and push ourselves to the limit.
Our love for the imperial style is in that we’re both coffee freaks—we really do enjoy those roasty complexities—as well as just being whiskey drinkers.
The barrel program here started pretty much when the pandemic hit—we were open in September 2019, six months before we got the whole system working the way we wanted and got the barrels filled. The first pair of barrels were actually on the Ides of March [2020], the night that the pandemic really did hit. In the taproom, the news came on, and everybody left. It was really eerie.
That started an era for us where we could brew those beers and put them into barrels, knowing that we didn’t necessarily have to have a customer to sell them to directly. Up front, the idea was to get as much diversity in barrels as we could potentially get, as well as the products themselves going into them.
About Those High-ABV “Super Monsters”
When you get into the mid-teens in ABV, some of those are actually single-fermentation. We ferment out as high as we can. But then, if it is one of those super monsters, we’re going to create a “smaller” beer first—basically like any of our other imperial stouts. However, we’ll mash even lower than a typical stout. What we’re trying to do is balance the osmotic pressure and all the stresses that the yeast will face during fermentation. We’ll ferment out as we normally do, but right as it stops, we’ll drop out whatever yeast are not going to feed beyond their alcohol tolerance. For our Scottish ale yeast, that’s about 14 percent. … We’re dumping the dead yeast because we don’t want autolysis, which will happen at these high osmotic pressure ranges, as well as at high ABV—those yeasts are not supposed to be subjected to that, but we’ll ferment it as dry as we can.
At that point, we introduce a diastatic strain, White Labs Super High Gravity Ale yeast, WLP099. This is where things get messy for a homebrewer. I recommend that you really do your homework with the STA1 diastatic gene. For us, we have the equipment and our specially made processes that we consider when doing this, to avoid cross-contamination.
We start the second fermentation right as the other one’s winding down. Then we start [the chaptalization]—usually with dextrose. Maple syrup is another one that’s very fermentable. Really, what we’re trying to do is ride the rate at which the yeast are feeding and to give them nothing more or less than what they’re actually eating day to day.
We use constant recirculation to keep things moving, to keep yeast introduced to the food, to keep the food suspended. Every time we feed, we take a gravity reading before and after, to measure what we’re actually putting in and making sure it’s being consumed. And we’re graphing the trends of the yeast to see what they’re doing with the consumables, and whether they’re going to continue on that trend. The idea is not to introduce any more sugar than they will eat because then you’re just sweetening the beer.
At that point, the beer is nutrient-deficient. It’s important that you treat the beer just like a sugar wash. You need to supplement with nutrients because that first fermentation scrubbed up all those good elements that were extracted from the mash itself. I recommend that homebrewers branch out and research different yeast nutrients—Fermaid O, diammonium phosphate, zinc—to understand where they’re needed. It’s really hard to overdo it with the big beers, but it can be done.
Once we see the fermentation petering out, we let it go to ambient temperature, as high as it can, because those yeast need anything to get those last fermentables. Ideally, we’re trying to match the end gravity to where it was after the first fermentation. Where that stopped, that terminal gravity, should be where you’re trying to end again.
Now, it’s a really hot beer at that point. This is still in stainless and hasn’t seen any barrel. Once you’re cracking that 20 percent ABV range, immediately on the taste, it’s pretty strong. You can tell there’s ethanol in it, and it’s got a thinner mouthfeel. We’ve already added another 10 percent of ethanol. People have to remember, as they’re feeding this thing—this monster they’re making in the tank—that it’s producing liquid volume, too. You have to make accommodations ahead of time for headspace.
You don’t really have to worry about oxygen uptake in the beginning and middle stages of this process—in fact, we’re actually adding oxygen during this whole process, on purpose. But after a noticeable decline in the metabolic rate, we cease any further purposeful introduction of oxygen. Any more oxidation we want is going to come from the barrel. In fact, we beg the barrel to do that because you have a 20 percent rocket-fuel product that really does need some time to mature—the oxidation helps level some stuff out. We give it as much time in there as it needs.
The most I’ve ever gotten out of this process was 24.5 percent ABV. That was Testify. And then we did a tequila-barrel variant, Conviction; the barrel got it up to 25 percent. And that’s when we learned that we can’t go higher than 22 percent ABV legally here in Missouri. So, that’s why our Beheading Leviathan is at 22 percent. Toward the end, we have to be careful because we never want to back-water the beer, to dilute it down to the limit.
We’re putting all these into barrels. If I’m brewing something to 20 percent ABV, there’s no way in hell I’m going to drink it unless I’m going to barrel-age it for a year or two. I don’t want to see it right then and there. It really does need some other secondary process, tertiary even, to help with that. We found the maturation process really helps to level out these monstrous beers.