Tasting Double
There are many classic beer styles that are well-known and enjoyed by beer lovers the world over. However, although classic beer styles provide a time-tested balance of ingredients, the strength of many has been held down by tax laws, government restrictions, the cost of ingredients and factors other than the preference of beer drinkers. Homebrewers have long been known for brewing their favorite beer style, but kicking it up a notch (or two (or three)).
These days, in the craft brew industry, there is a trend towards releasing bigger versions of many beer styles. These beers are often denoted with the moniker “double” or “imperial.” These terms don’t have any specific definition — “double” doesn’t literally mean double the amount of malt in most cases. Likewise, the word “imperial” means “of or relating to an empire” in everyday usage, but in beer styles the usage follows from the term “imperial stout” — a bigger version of a regular stout. A double or imperial beer is simply a bigger, more robust version of a given style of beer.
In this recipe collection, we present clones of five commercial beers that are double or imperial versions of five different classic beer styles — a Pilsner, Oktoberfest, IPA, porter and stout — based on information provided to us by the breweries. Although the extra “weight” adds brewing challenges, the results can be rewarding.
It’s in “dubbly”
If you are interested in making your own double or imperial beer, there are a few rules that can help you make good decisions during recipe formulation. First, as mentioned earlier, a double or imperial beer is not simply created by doubling a recipe. Usually the amount of grain required is less than twice that of the beer being doubled (or “imperialized”). Left Hand Brewery, for example, uses 800 kilos of grain to make a 22-barrel batch of their Twin Sisters Double IPA, while their Warrior (“regular”) IPA uses 500 kilos.
In any case, the biggest challenge is balancing the flavor characteristics representative of the base style with the increased alcohol levels caused by a larger malt bill. When striving for a balance of flavors, the percentage of specialty malts needs to be considered. Specialty malts (and dark roasted grains) may be scaled up at the same rate as the recipe as a whole, but usually the more intensely-flavored specialty grains are scaled up less than proportionally. This avoids having the more darkly-kilned malts come to dominate the flavor profile of the beer and not represent the flavor profile of the base beer style. There is no simple formula to follow when scaling up specialty grains for an imperial version of a regular beer style. You will just need to use your judgement and experiment to get the right balance of flavors appropriate to the base style and increased alcohol due to the “doubling.”
As with the malt, hopping rates should be increased to balance the bigger malt presence and higher alcoholic strength. Similar to specialty malts, there’s no magic formula for how much you need to increase your hopping rate. Keep in mind also that the amount of grain in your recipe affects your hop utilization — the higher the gravity you boil your wort at, the lower your hop utilization. Getting the right balance can be tricky, so plan to brew at least one test batch before settling on your recipe. And of course, consulting existing double or imperial recipes may help guide your own recipe formulation decisions.
Mashing Matters
For all-grain brewers, making a double or imperial beer may require some changes to their procedures. At a minimum, more grain will be mashed, so before you start, be sure you have enough space in your mash tun to avoid any nasty surprises on brewday. As a rough guide, for every 10 pounds of grain in your recipe, you will need at least 4 gallons of space in your mash tun (~3.33 L/kg). In the case of very big beers, you may need to employ more than one mash tun (or to mash and lauter in shifts). For very big beers, you will also need to collect more wort and boil it for a longer time, or your extract efficiency will suffer. As a rule of thumb, expect to collect a little over a gallon of wort for every 2.0 pounds of grain in the recipe (~4.2 L/kg). With a propane burner, at a homebrew scale, it is easy to boil off a gallon (3.8 L) of wort an hour and not overly darken the wort. For very big beers, you may need more than one kettle.
Of course, you can also skip the long, huge boil by simply collecting enough wort for a normal-length boil, then adding malt extract to reach your target specific gravity. You can also add a great excess of malt and make your beer from only first runnings.
Extract brewers simply need to add the required amount of malt extract to reach their target specific gravity. The biggest challenge for extract brewers, when making any big beer, is to get adequate hop bitterness and to keep color pickup in the boil to a reasonable range. The solution in both cases is to increase the boil volume to minimize the effect of boiling a highly concentrated wort. The most preferable option is to do a full-wort boil. If that isn’t possible, boil the largest volume you can.
Pitch perfect
For optimal yeast performance when pitching to a high-gravity wort, it is important to give the yeast everything possible so it has a fighting chance. Make sure the yeast strain is designed to handle high-gravity beers. Most beer strains will do fine up to 10–12%, but if you’re brewing a real monster, check the yeast descriptions carefully.
Make a large yeast starter or pitch an adequate amount of yeast harvested from a previous fermentation. As a rough rule of thumb, a yeast starter for 5 gallons (19 L) of “normal-strength” ale (around 12 °Plato/SG 1.048) should be 1.5–2 quarts (~1.5–2 L). The size of the starter should scale proportionally with the gravity of the beer. If you don’t make a starter, you should pitch two (or more) packages of yeast.
The next step is to oxygenate. Yeast needs oxygen too, and in this case one heck of a lot to stay alive long enough to breakdown all that sugar. If you have an oxygen tank, get the tube in the carboy and really bubble away for a couple minutes. If you are like me, shake shake shake the carboy until you think your arm might fall off. Rest a couple minutes, and repeat. This should be done at least four or five times — really!
Patience, Grasshopper
Because of the high gravity of these beers, fermentation usually takes a few extra days. Give the beer time to finish fermenting and to condition and don’t rush it into the bottle. It can be hard to wait, but it will be worth it.
Double/Imperial Recipes
Odell Brewing Company: Double Pilsner clone
(5 gallons/19 L, all-grain)
OG = 1.076 FG = 1.017
IBU = 37 SRM = 4 ABV = 8.2%
Like a double IPA, this is a amped up version of a Pilsner from Odell Brewing.
Ingredients
14.5 lbs. (6.6 kg) German Pilsner malt
1 lb. (0.45 kg) Weyermann Carafoam® malt (2 °L)
4 oz. (113 g) Munich malt (10 °L)
10 AAU Saaz hops (60 min.) (2.9 oz./81 g at 3.5% alpha acids)
5.7 AAU Tettnang hops (1 min.) (1.5 oz./43 g at 3.8% alpha acids)
5.7 AAU Tettnang hops (0 min.)
(1.5 oz./43 g at 3.8% alpha acids)
1 tsp Irish moss (15 min.)
Wyeast 2206 (Bavarian Lager) or White Labs WLP820 (Octoberfest/ Märzen) yeast (4 qt./4 L starter)
¾ cup (150 g) dextrose (if priming)
Step by Step
Use water with a low mineral content. Mash crushed grains with 5 gallons (19 L) of mash water, heated to 162 °F (72 °C). Mash at 150–152 °F (66–67 °C) for 45 minutes. Recirculate wort until it is quite clear. Collect wort, sparging with 168 °F (76 °C) water to collect 6.5 gallons (25 L) of wort. (Your SG here should be 1.058. If it’s lower than this, add dried malt to reach 1.058 or collect more wort — up to 8 gallons/30 L — and boil longer). Boil wort for 90 minutes, adding the hops at times indicated. At the end of the boil, turn off heat, add the final hop addition and stir the wort to create a whirlpool. Allow the wort to settle for 10 minutes. Cool wort, transfer to fermenter and aerate well. Pitch yeast sediment from yeast starter. Ferment beer at 55 °F (13 °C). Hold fermentation temperature until beer is finished fermenting. Chill to 34 °F (1.1 °C) and hold for at least a month. Prime bottles with sugar or keg.
Extract with grains option:
Reduce the German Pilsner malt in the all-grain recipe to 0.75 lb. (0.34 kg) and add 2 lbs. (0.91 kg) Briess extra light dried malt extract and 6.6 lbs. (3 kg) Briess Pilsen liquid malt extract. Put crushed grains in a nylon steeping bag. In a large soup pot, heat 3 qts. (2.8 L) of water to 162 °F (72 °C) and submerge bag. Steep grains at 150–152 °F (66–67 °C) for 45 minutes. While grains are steeping, bring 2.5 gallons (9.5 L) of water to a boil in your brewpot. After steep, put colander over brewpot and place grain bag in it. Pour “grain tea” through grain bag (to filter out the “floaties”), then rinse grains with 1.5 quarts (1.4 L) of water at 170 °F (77 °C). Add dried malt extract and boil wort for 60 minutes, adding hops at times indicated. Add liquid malt extract at the end of the boil and let it steep for 15 minutes before cooling. Top off to 5 gallons (19 L). Follow the remaining portion of the all-grain recipe.
Avery Brewing Co.’s The Kaiser (Imperial Oktoberfest) clone
(5 gallons/19 L, all-grain)
OG = 1.085 FG = 1.015
IBU = 23 SRM = 11 ABV = 9.7%
Ingredients
11.5 lbs. (5.2 kg) 2-row pale malt
2.1 lbs. (0.95 kg) Weyermann Vienna malt
2.1 lbs. (0.95 kg) Weyermann Munich Type I malt (7 °L)
1.4 lbs. (0.64 kg) Gambrinus dark Munich malt (20 °L)
11 oz. (312 g) Dingemans aromatic malt
4.75 AAU Hallertau Tradition hops (60 min.) (0.6 oz./17 g of 2.7% alpha acids)
4.75 AAU Magnum hops (60 min.) (0.2 oz./6 g of 13.6% alpha acids)
2.5 AAU Sterling hops (30 min.) (0.4 oz./11 g of 6% alpha acids)
0.5 oz. (14 g) Tettnang hops (0 min.)
0.5 oz. (14 g) Hallertau Hersbrücker hops (0 min.)
Wyeast 2206 (Bavarian Lager) or White Labs 820 (Octoberfest/Märzen) or Saflager 34/70 yeast (4 qt./~4 L yeast starter)
¾ cups corn sugar (if priming)
Step by Step
Mash the grains at 152 °F (67 °C), using 5.6 gallons (21 L) of mash liquor heated to 163 °F (73 °C). Mash in, mix for 20 minutes, then rest for 20 minutes. Vorlauf (recirculate) for 15 minutes. Collect 7 gallons (26 L) of wort and check specific gravity (SG). If SG is below 1.061, you can either add dried malt extract to make it 1.061 or collect more wort — up to 9 gallons (34 L) — and extend the boil time accordingly. Boil for 120 minutes, adding the hops at the times indicated in the ingredients list. After the boil, turn off the heat and chill the wort rapidly to 55 °F (13 °C), aerate well and pitch the yeast. Ferment at 55 °F (13 °C) for the first 24 hours, then drop the temperature to 50 °F (10 °C). When the gravity hits 1.030-1.035, let the temperature rise to wherever it can for diacetyl rest. When primary fermentation is complete, bottle or keg as normal.
Partial Mash Option: Omit the 2-row malt, scale both the Wyermann Vienna malt and Wyermann Munic Type I malts to 1 lb. 4.2 oz, (0.57 kg) each. Add 3.0 lbs. (1.4 kg) Coopers Light dried malt extract and 6 lbs. (2.7 kg) Coopers Light liquid malt extract (late addition). Heat 5.5 quarts (5.2 L) of water to 166 °F (74 °C) and pour into 2-gallon (7.6-L) beverage cooler. Place crushed grains in a nylon steeping bag and submerge. Stir grains well, tie off bag lightly and seal cooler. Let partial mash rest, starting at 155 °F (68 °C), for 45 minutes. (It will most likely drop to around 150 °F (66 °C) by the end of the mash. This is fine.) While partial mash is resting, heat 0.75 gallons (2.8 L) of water to a boil in your brew pot and 5 qts. (4.7 L) of water to 180 °F (82 °C) in a large kitchen pot. Run off first wort and add to boiling water in brew pot. Add the 5 qts. (4.7 L) of 180 °F (82 °C) water to the cooler, untie bag, stir grains and let sit for 5 minutes. Run off second wort and add to brewpot. Add dried malt extract and bring to a boil. Add first charge of hops and boil for 60 minutes, adding other hops at times indicated in the ingredient list. With 15 minutes left in the boil, stir in half of the liquid malt extract; add the remaining half at the end of the boil. (Keep the boil clock running when adding extract.) Let the wort sit for 15 minutes before cooling. Cool the wort and top up with enough cool water to make 5 gallons (19 L), aerate well and pitch yeast. Follow fermentation and lagering instructions in all-grain recipe.
Left Hand Twin Sisters (Double IPA) Clone
(5 gallons/19 L, all-grain)
OG = 1.085 FG = 1.016
IBU = 87 SRM = 10 ABV = 9.1%
Ingredients
15 lbs. (6.8 kg) Castle pale ale malt
1.5 lbs. (0.68 kg) rye malt
0.5 lbs. (0.23 kg) biscuit malt
0.5 lbs. (0.23 kg) crystal malt (40 °L)
13.75 AAU Tomahawk hops (60 min.) (0.92 oz./26 g of 15% alpha acids)
7.5 AAU Glacier hops (45 min.) (0.63 oz./18 g of 12% alpha acids)
3.75 AAU Cascade hops (30 min.) (0.75 oz./21 g of 5% alpha acids)
3.75 AAU Liberty hops (15 min.) (0.94 oz./27 g of 4% alpha acids)
3.0 AAU Liberty hops (5 min.) (0.75 oz./21 g of 4% alpha acids)
1.25 oz. (35 g) Crystal hops (dry hop)
Wyeast 1272 (American Ale II) or White Labs WLP051 (California Ale V) yeast (3 qt./~3 L yeast starter)
0.75 cups corn sugar (for priming)
Step by Step
Mash at 152 °F (67 °C). Boil for 90 minutes. Ferment at 68 °F (20 °C).
Left Hand Twin Sisters (Double IPA) Clone
(5 gallons/19 L, partial mash)
OG = 1.085 FG = 1.016
IBU = 87 SRM = 10 ABV = 9.1%
Ingredients
3.5 lbs. (1.6 kg) Muntons light dried malt extract
6.5 lbs. (3.0 kg) Muntons light liquid malt extract (late addition)
1.5 lbs. (0.68 kg) rye malt
0.5 lbs. (0.23 kg) biscuit malt
0.5 lbs. (0.23 kg) crystal malt (40 °L)
13.75 AAU Tomahawk hops (60 min.) (0.92 oz./26 g of 15% alpha acids)
7.5 AAU Glacier hops (45 min.) (0.63 oz./18 g of 12% alpha acids)
3.75 AAU Cascade hops (30 min.) (0.75 oz./21 g of 5% alpha acids)
3.75 AAU Liberty hops (15 min.) (0.94 oz./27 g of 4% alpha acids)
3.0 AAU Liberty hops (5 min.) (0.75 oz./21 g of 4% alpha acids)
1.25 oz. (35 g) Crystal hops (dry hop)
Wyeast 1272 (American Ale II) or White Labs WLP051 (California Ale V) yeast (3 qt./~3 L yeast starter)
0.75 cups corn sugar (for priming)
Step by Step
In your brewpot, heat 3.5 quarts (3.3 L) of water to 163 °F (73 °C). Add crushed grains to a nylon steeping bag and steep for 45 minutes at 152 °F (67 °C). While grains are steeping, heat 1.5 quarts (1.4 L) of rinse (sparge) water to 170 °F (77 °C). After steep, put a colander over your brewpot and put the grain bag in it. Rinse grains with 170 °F (77 °C) sparge water. Add water to brewpot to make 4.0 gallons (15 L). (If you boil a smaller volume, you will not be able to extract the proper amount of bitterness from the hops.)
Bring “grain tea” and water to a boil and add dried malt extract. Boil for 60 minutes, adding hops at times indicated in the ingredient list. Keep a smaller pot of boiling water handy, and keep the boil volume topped up to 4.0 gallons (15 L). Stir in the liquid malt extract at the end of the boil and let it steep for 15 minutes before cooling. Cool wort and transfer to fermenter. Top up to 5 gallons (19 L) with cool water and aerate thoroughly. Pitch yeast and follow fermentation instructions in all-grain recipe.
Flying Dog Brewery: Gonzo Imperial Porter clone
(5 gallons/19 L, all-grain)
OG = 1.088 FG = 1.025
IBU = 75 SRM = 57 ABV = 9%
Brewed in honor of Hunter S. Thomson, this beer is “big, bold, and beautiful.” It features notes of roasted chocolate, coffee, and vanilla malt flavors.
Ingredients
15 lbs. (6.8 kg) 2-row pale malt
2.5 lbs. (1.1 kg) crystal malt (120 °L)
1 lb. (0.45 kg) black malt
0.5 lb. (0.23 kg) chocolate malt
5.5 AAU Warrior hops (90 min.) (0.34 oz./9.7 g of 16% alpha acids)
9.4 AAU Northern Brewer hops (60 min.) (1 oz./28 g of 9% alpha acids)
9.4 AAU Northern Brewer hops (30 min.) (1 oz./28 g of 9% alpha acids)
3 oz. (85 g) Cascade hops (0 min.)
4 oz. (114 g) Cascade hops (dry hop)
Wyeast 1056 (American Ale) or White Labs WLP001 (California Ale) yeast (3 qt./~3 L yeast starter)
3⁄4 cups (150 g) dextrose (for priming)
Step by Step
Crush the grains and mash at 152 °F (67 °C) for 60 minutes. Mash out, vorlauf, and then sparge at 170 °F (77 °C) to collect enough wort to result in 5 gallons (19 L) after a two-hour boil. Boil two hours, adding the hops as directed. Cool, aerate, and pitch yeast. Ferment at 70 °F (21 °C). After fermentation is complete, bottle or keg as usual.
Partial mash option:
Substitute the 2-row pale malt in the all-grain recipe with 3 lbs. (1.4 kg) Briess light dried malt extract and 6.75 lbs. (3.1 kg) Alexander’s pale liquid malt extract. Heat 5.5 quarts (5.2 L) of water to 166 °F (74 °C) and pour into 2-gallon (7.6-L) beverage cooler. Place crushed specialty grains in a nylon steeping bag and submerge. Stir grains well, tie off bag lightly and seal cooler. Let grains steep, starting at 155 °F (68 °C), for 30 minutes. While grains are steeping, heat 2 gallons (7.6 L) of water to a boil in your brewpot and 2.5 qts. (2.4 L) of water to 180 °F (82 °C) in a large kitchen pot. Run off “grain tea” and add to boiling water in brewpot. Add the 2.5 qts. (2.4 L) of 180 °F (82 °C) water to the cooler, untie bag, stir grains and let sit for 5 minutes. Run off remaining “grain tea” and add to brewpot. Add dried malt extract and bring to a boil. Add first charge of hops and boil for 60 minutes, adding other hops at times indicated in the ingredient list. With 15 minutes left in boil, stir in half of the liquid malt extract; add the remaining half at the end of the boil. Let wort sit 15 minutes before cooling. Cool wort and transfer to fermenter. Add water to make 5 gallons (19 L). Follow the remaining portion of the all-grain recipe.
Great Divide Yeti Imperial Stout clone
(5 gallon/19 L, all-grain)
OG = 1.090 FG = 1.018
IBU = 75 SRM = 60 ABV = 9.5%
Ingredients
15.25 lbs (6.9 kg) American 2-row malt
1.0 lb (0.45 kg) crystal malt (120 °L)
12 oz. (0.34 kg) chocolate malt
12 oz. (0.34 kg) black patent malt
10 oz. (0.28 kg) roasted barley
8.0 oz. (0.23 kg) flaked wheat
8.0 oz. (0.23 kg) flaked rye
14.3 AAU Chinook hops (60 min.) (1.1 oz./31 g of 13% alpha acids)
7.2 AAU Chinook hops (30 min.) (0.55 oz./16 g of 13% alpha acids)
5.3 AAU Centennial hops (15 min.) (0.50 oz./14 g of 10.5% alpha acids)
0.5 oz. (14 g) Centennial hops (5 min.)
Wyeast 1056 (American Ale) or White Labs WLP001 (California Ale) yeast (3 qt./~3 L yeast starter)
0.75 cups corn sugar (for priming)
Step by Step
Mash at 150 °F (66 °C). Boil for 60 minutes, adding hops as indicated above. Ferment at 70 °F (21 °C).
Partial Mash Option
Reduce the amount of 2-row pale malt to 2.0 lbs. (0.91 kg). Add 9.0 lbs. (4.1 kg) of Mun-tons Light liquid malt extract to the recipe. Heat 2.3 gallons (8.7 L) of water to 161 °F (72 °C). Submerge grain bag(s) and partial mash at 150 °F (66 °C) for 30–45 minutes. (Note: this is just over 6 lbs. (~ 3 kg) of grains, you may need more than one grain bag, depending on size. Putting your brewpot in your oven on its lowest heat setting may help you maintain partial mash temperature.)
Remove grains, rinse grain bag(s) slowly with 1.0 gallon (3.8 L) of water at 170 °F (77 °C). Add water to brewpot to make 4.0 gallons (15 L) of wort; stir in roughly two-thirds of the malt extract. Bring to a boil. Boil for 60 minutes, adding hops at the times indicated in the ingredient list. Add remaining malt extract with 15 minutes left in boil. Cool wort, transfer to fermenter, top up to 5 gallons (19 L), aerate and pitch yeast. Ferment at 70 °F (21 °C).
