What Should be in Your Fermenter (Russian Imperial Stout)

By Aaron Fournier

Sweet like crude. Dark as night. Roastier than Chock Full O’ Nuts. Oh yeah, we’re talking Imperial Stouts. Many commercial examples of Russian Imperial Stout have the history of the style right there on the bottle, so I won’t bore you with that. Whether you fancy the beautiful, economical, and tasty Old Rasputin or Black Chocolate Stout, or favor the bigger and rarer guys like Dark Lord or Bourbon County Stout, I’m here to help you brew it. And save some serious coin in the process.

Speaking of process, we should probably tackle that right off the bat. You know, before you start your second bottle of Old Rasputin while reading this.

In my opinion, the difference between “ok” high alcohol beers and “awesome” high alcohol beers boils down to just two things. Proper aging before consuming, and adding enough yeast to do the job well. So now let’s dive in.

I prefer to brew my big beers in the opposite season in which I’m going to consume them. So even though only brave souls can drink Imperial Stouts in the heat of Summer that is exactly when I want to brew one. Your average beer is ready to go in about four weeks. I like to tack on two weeks of aging for every percent of alcohol above 5% ABV. So for a 10% ABV Imperial Stout, you’re talking 14 weeks, or 3 ½ months. Keep in mind that this is just a guideline for minimum aging times; the higher the alcohol content, the more time it’s going to need. For a 9-10% ABV beer, go 3-4 months. For 11-15% ABV beer, go 5-8 months. So now we have our aging guidelines, let’s talk about yeast.

Big beers need a lot of yeast. That should go without saying. Simply pitching a single pack of yeast is going to cause the yeast to struggle and throw off-flavors you really don’t want in your beer. Not only that but, more than likely, the yeast is going to die due to stress and the high alcohol before fermentation finishes, leaving you with a sticky and sweet gravy of a beer. When you keep the alcohol at or below 11% ABV, your only worry is pitching enough ale yeast. For a beer of 8-11% ABV, three packs of yeast are not only required, but it wouldn’t hurt to pitch four. For real. One thing homebrewers rarely think about is flocculation of the yeast with regards to how it effects the yeast finishing fermentation. For example, one of my favorite strains is Wyeast 1968 London ESB/White Labs 002. This yeast has a tremendous flavor profile for a variety of beers (including Imperial Stouts!) and it clears (flocculates) better than any other yeast out there. Cause who likes cloudy beer? The major drawback of the high flocculation rate of this yeast is that it can drop out of solution before the job is actually done. If using highly flocculating yeast, go four packs of yeast. If using something with medium flocculation, like Wyeast 1056/White Labs 001, three packs ought to do it. See where I’m going with this?

But let’s say you want to brew the big boys. The REALLY big boys. Something tipping the scale above the ability of normal ale yeast. Something in the 12-15% ABV range. Now we’re venturing into putting our beer into two separate fermentations, and I’m not talking about a “secondary fermentation”. We need two separate primary fermentations. First we are going to pitch mucho ale yeast into our primary fermenter, at least 4-5 packs (depending on the 12-15% scale, I’m sure you can do that math). After our first primary fermentation comes to a stop, we need to transfer the beer to a fresh fermenter. We’re going to need head-space, so DO NOT simply transfer it into a 5-gallon carboy as if you were doing a secondary. Use another bucket or a 6-6.5 gallon carboy. We then need to pitch a yeast that can handle the challenging conditions of a high alcohol environment. Champagne yeast is the most common strain used to finish off high alcohol beers. I also like to use a strain called K1V-1116. This strain excels at fermenting in conditions that would kill or otherwise hamper other strains of yeast. Both champagne yeast and K1V are wine strains, but since the majority of your yeast character has already been born, they are simply going to finish the job of fermentation, not make your beer taste like wine. This is a common technique used by many breweries to make sure big beers finish fermenting.

So now that we’ve got the basics down, let’s brew it. Below you’ll find a “moderate” (by today’s standards) Russian Imperial Stout recipe (keep an eye out for a beer nerd fantasy Russian Imperial Stout recipe in a forthcoming post).

Oh That Putin! (Old Rasputin Russian Imperial Stout) 9%-ish ABV

This one is going to be a balanced Russian Imperial Stout, with big hop notes, but in a balanced kind of way. Lots of body, but dangerously drinkable. These strength Russian Imperial Stouts are pretty straight forward, so here’s the goods.

For 5 Gallons

All-Grain:
Mash at 151 F
60 Minute Boil

Extract with Grains:

If bottling, either bottle fresh and age for 2-3 months before opening. Or, secondary in a 5 gallon carboy for 2 months. Then pitch a fresh pack of yeast and bottle as usual. Once bottles are carbonated (normal two weeks usually), crack open and enjoy. If kegging, secondary for 3 months, then keg and carbonate as usual.

And now you’d want to talk about brewing the big boys like Dark Lord or Bourbon County. Maybe even KBS or Parabola. Well, that blog post is coming soon. Trust me, it is coming soon. Stay thirsty!