Recipe

Smoked “Imp” Imperial Stout

(5 gallons/19 L, all-grain)
OG = 1.092  FG = 1.018
IBU = 55  SRM = 57  ABV = 9.6%

I like to make my imperial stouts on the dry/thin side so I mash low, but feel free to raise your mash temperature, or add some rolled oats for more of a “wet” stout with added mouthfeel. I also purposely used lighter sugar, specialty malts and a clean yeast strain to let the smoked malt shine.- Mark Zappasodi

Ingredients
11.5 lbs. (5.2 kg) Crisp Maris Otter malt
1.5 lbs. (0.68 kg) Caramunich® Type I malt
1.0 lb. (0.45 kg) crystal malt (60 °L)
8.0 oz. (0.23 kg) light chocolate malt
8.0 oz. (0.23 kg) roasted barley
2.0 lbs. (0.91 kg) Briess Cherry Wood Smoked Malt
1.0 lb. (0.45 kg) light brown sugar (15 min.)
¼ cup molasses (0 min.)
½ tsp. Wyeast yeast nutrient (10 min.)
1 WhirlFloc® tablet (15 min.)
5.5 AAU Galena hops (FWH) (0.5 oz./14 g of 11% alpha acids)
11 AAU Galena hops (90 min.) (1 oz./28 g of 11% alpha acids)
1 oz. (28 g) Fuggle hops (0 min.)
White Labs WLP001 California Ale (1 qt./1 L yeast starter)

Step by Step
Mash in with 166–168 °F (74–76 °C) water to settle at 149–150 °F (65–66 °C) for 60 minutes. Raise temperature to 168–170 °F (76–77 °C) for ten minutes. Sparge with 175 °F (79 °C) water for 60–90 minutes. Add first wort hops and collect at least 7 gallons (26 L) of wort to be boiled for 90 minutes. Cool quickly to 65 °F (18 °C) and pitch yeast. Let temperature raise naturally to between 68 and 70 °F (20–21 °C) and hold. This beer should take 7 to 10 days to complete and then rack to secondary for a week to ten days. Keg at 10 PSI or bottle with 1 cup of corn sugar in 750 mL corked and hooded bottles. This beer will age well for years or can be consumed in a few weeks after bottling.

Smoked “Imp” Imperial Stout

(5 gallons/19 L, partial mash)
OG = 1.092  FG = 1.018
IBU = 55  SRM = 57  ABV = 9.6%

Ingredients
0.5 lbs. (0.23 kg) Crisp Maris Otter malt
1.5 lbs. (0.68 kg) Caramunich® Type I malt
1.0 lb. (0.45 kg) crystal malt (60 °L)
8.0 oz. (0.23 kg) light chocolate malt
8.0 oz. (0.23 kg) roasted barley
2.0 lbs. (0.91 kg) Briess Cherry Wood Smoked Malt
1.0 lb. (0.45 kg) light brown sugar (15 min.)
¼ cup molasses (0 min.)
½ tsp. Wyeast yeast nutrient (10 min.)
1 WhirlFloc® tablet (15 min.)
5.5 AAU Galena hops (FWH) (0.5 oz./14 g of 11% alpha acids)
11 AAU Galena hops (90 min.) (1 oz./28 g of 11% alpha acids)
1 oz. (28 g) Fuggle hops (0 min.)
White Labs WLP001 California Ale (1 qt./1 L yeast starter)

Step by Step 
For the partial mash adaptation of this recipe, you will need a 3.0-gallon (11-L) beverage cooler (with a spigot) and a grain bag capable of holding 6.0 lbs. (2.7 kg) of grain. Place crushed grains in the large steeping bag and place in the cooler. Heat 8.2 qts. (7.8 L) of water to 161 °F (72 °C) and stir into grains so that the temperature hits 149–150 °F (65–66 °C). Place lid on cooler and hold at this temperature for 60 minutes. Collect wort and sparge with 190 °F
(88 °C) water by drawing off 2–3 cups (470–710 mL) of wort and adding it to your brewpot, then gently pouring the same amount of hot water to the top of the grain bed in the cooler. Repeat until you have collected 3.0–3.5 gallons (11–13 L) of wort. Add first wort hops (FWH) while collecting wort. Add roughly half of the malt extract and boil wort for 90 minutes. (Keep some boiling water handy and don’t let the boil volume dip below 3.0 gallons/11 L.) Add hops at times indicated and carefully stir in remaining malt extract in final 15 minutes of the boil. Cool wort quickly to 65 °F (18 °C) and pitch yeast. Let temperature raise naturally to between 68 and 70 °F (20–21 °C) and hold. This beer should take 7 to 10 days to complete and then rack to secondary for a week to ten days. Keg at 10 PSI or bottle with 1 cup of corn sugar in 750 mL corked and hooded bottles. This beer will age well for years or can be consumed in a few weeks after bottling.

Tips for Success
When making a dark beer, water chemistry can make the difference between a beer that seems too acidic and one in which the roasted flavors taste pleasant. If you were starting from distilled water, adding 0.25 oz. (7.1 g) of calcium carbonate (chalk) and 0.25 oz. (7.1 g) of sodium bicarbonate (baking soda) per 5 gallons (19 L) of brewing liquor (brewing water) would benefit this beer. (If you have a pH meter, check the mash pH. It should fall between 5.2 and 5.6.)

Also, as with any big beer, thorough wort aeration, adding some yeast nutrients in the boil and making a yeast starter will yield a better fermentation.

I like to make my imperial stouts on the dry/thin side so I mash low, but feel free to raise your mash temperature, or add some rolled oats for more of a “wet” stout with added mouthfeel.