Homebrew Imperial Stout

By: Jesse Reynolds

It’s the most wonderful time of the year.
That’s right, about a month before the holidays when all the craft breweries seem to release
their barrel-aged Imperial Stouts at the same time.
Rich, roasty, warm and smooth; this jet-black beer hits all the right notes for a cold winter’s night
huddled with friends by the fire. Emphasis here is on the word “friends”, because this is exactly
the kind of beer that you don’t want to drink alone.
Far from simplistic, it pours syrupy and viscous like motor oil with a big brown head, smells like
coffee and chocolate, with complex flavours of roasted malt, high hop bitterness and dark fruit
character. Young versions finish with alcohol warming, but this stuff only gets better with age; a
year or two in the cellar and it will go down smooth and sweet like a nice dessert beer.
The style dates back hundreds of years to when England first shipped a highly-alcoholic, hoppy
version of porter to Russia, but in recent times it has become distinctly and profoundly
American. That is to say that craft brewers have taken this historic beer and made it their own,
with great success.
In short, Imperial Stouts are kind of a big deal, especially the barrel-aged variety.
So, how to go about brewing one? Very delicately. Achieving the depth of flavour and balance
required from the style is like walking a tightrope. Fermenting the amount of sugar needed to
make a beer this big can also be a challenge.
Let’s start with malt. To achieve the kind of complexity and richness we’re seeking, we want a
good British base malt with layers of specialty malts that lean heavily toward the dark side.
Maris Otter fits the bill for base malt, along with Crystal 120 (fruit, burnt caramel) Carapils (adds
body, head), Roasted Barley (chewy, roasty), Dark Chocolate (chocolate, coffee) and Carafa III
(darkness, bitterness without astringency).
To balance all this malt character, we require an assertive amount of neutral hops that won’t be
overbearing. Northern Brewer and Cluster hops will provide a woody, earthy and fruitiness in
addition to a moderate bitterness. East Kent Goldings hops will add herbal and floral notes to
the aroma.
Lastly, the barrel-aging component. If you can find a used whisky barrel, that’s great. Otherwise,
soaking oak cubes or chips in bourbon is a decent option.
Alternatively, buy a bottle of your favourite whisky or bourbon and pour 1-2oz per gallon of beer
into the packaging vessel. Craft brewers can’t afford to do this, but on a homebrew scale it’s
possible; the most effective way to impart flavours of oaked whisky is to add oaked whisky!

Imperial Stout (BJCP Category 20C)
(all-grain, 5.5 gallons)
OG: 1.110
FG: 1.024

ABV: 11.24%
IBU: 81
SRM: 50
Water
9 Gallons Tap Water (treated w/ campden tablets) or Spring Water
Add 1 tsp Calcium Carbonate, ½ tsp Gypsum and ½ tsp Calcium Chloride to mash

Malt
15lb Maris Otter
2lb Crystal 120
1lb Carapils
1lb Roasted Barley
1lb Dark Chocolate Malt
0.5lb Carafa III
1lb Brown Sugar (15 mins remaining in boil)

Hops
2oz Cluster (60 mins)
2oz Northern Brewer (60 mins)
1oz Cluster (5 mins)
1oz East Kent Goldings (5 mins)

Yeast
White Labs WLP001 California Ale or Escarpment Labs Cali Ale
5 tsp Yeast Nutrient (15 mins remaining in boil)
Note: To achieve an adequate amount of yeast cells to ferment this beer, start a week before
brew day and build a 2L starter at 1.045 OG. After 72 hours, chill and decant the starter and
pour in another 2L of 1.045 wort. Within another 72 hours, you should have enough yeast cells
to ferment the beer.

Brew Day Instructions
Mash-in grains with 6.5 gallons of water to reach 152F (67C) and hold for 90 minutes, then raise
temperature to 168F (76C) and hold for 10 minutes. Sparge very slowly with 168F water until
you have 7 gallons of wort in your kettle.
Boil for 90 minutes, adding hops, brown sugar and yeast nutrient as directed above.

After flameout, cool to 68F (20C) rapidly and oxygenate vigorously before pitching yeast.
Ferment at 68-70F for 14 days, and check if beer has reached FG. If it stalls at any point above
10% ABV, re-pitching with WLP 009 Super High Gravity yeast may be necessary to finish the
beer.
Optional – ‘barrel-age’ your beer as noted above.
Finally, package in bottles with priming sugar, or carbonate in a keg and bottle. Enjoy fresh, or
age up to three years (the sweet spot for drinking is one to two years). Waxing your bottle caps
is a good way to prevent oxidation and preserve carbonation over time.