Black Flannel Academy

Imperial Stout

A bold, malty black beer featuring chocolate, roasty, and coffee flavors with a large range of expressions depending on region and taste. Some, particularly American expressions, will feature substantial bitterness and hop aroma with a less fruity yeast profile, while English versions tend to favor a malt balance with more fruity esters.

Roasty

Full Body

Esters

Piney

Color

Straw

Gold

Amber

Dark Amber

Brown

Black

Straw

Black

Black / 30 – 40 SRM

Perceived Bitterness

Very Low

Low

Moderate

Pronounced

Assertive

Highly Assertive

Very Low

Highly Assertive

Pronounced / 50 – 90 IBU 

0%

3%

6%

9%

12%

15%

0%

3%

6%

9%

12%

15%

ABV 8 – 12% (OG 1.075 – 1.115 with FG 1.018 – 1.030)

Sweetness

Low (Dry)

Medium

High

Low (Dry)

Medium

High

Sweetness Medium

Balance

Malty

Balanced

Hoppy

Malty

Balanced

Hoppy

Balanced between Malty & hoppy

HISTORY

The origins of imperial stout are tied tightly to the history of porter in eighteenth-century England (think decorative lights in National Lampoon’s Christmas Vacation tight). You can see our post on porter for a bit more info on how that beer became so popular, but once it was the hot commodity in northern Europe, the bigger commercial breweries in London began brewing an imperial version for export to the Baltic region (Lithuania, Latvia, and Estonia) and Russia. 

Exported versions of any style were often brewed with significantly higher hopping rates (10 lb/bbl in the early imperial stouts for you hop heads out there!) and a higher alcohol content for their long journey to those countries. There is now some discussion among beer writers as to whether styles like this, including IPA, evolved as a purely practical matter–they needed the alcohol and bitter hop acids to combat infection–or if other factors were at play. Whatever the case, the story goes that the Russian court, and specifically Catherine the Great, loved the style. We don’t blame her…this stuff will warm your soul, and we need all the help we can get for about eleven months each year in northern Vermont.

Imperial stout helped break the trend of flavorless canned fizzy water here in the states (respect) when Merchant du Vin asked the folks at England’s Samuel Smith Brewery to make an imperial stout for the American market. Craft producers became interested in brewing it, and American consumers obliged. Although it might be hard to imagine, the style as we know it today is relatively young and evolving quickly. American brewers have done just about anything you could imagine to imperial stouts, including aging them on fruit and spices, brewing them with hot peppers and sauces, and aging them in spirit and wine barrels (these are some of our favorite versions here in the brewery). Over the past several years, a new trend of culinary-inspired imperial stouts have exploded in the craft beer world, including beers that taste like s’mores, black forest cake, vanilla truffles, and cinnamon rolls to name a few.

Imperial stout is a beer that requires patience. Patience on brew day, patience as it conditions to perfection, patience when you open a bottle and sip it by the fire, and, if you’re able, patience to age a few of them for several years and see how they change.

CLASSIC CHARACTERISTICS:

Aroma – Chocolate (dark or milk), coffee, roast. Large variety of possible hop characters including citrus, pine, and fruit from American examples or earthy, herbal, and floral for European examples. Large variety of possible yeast characters ranging from clean to very fruity.

Appearance – Deep, opaque, black. A few English examples can be very deep brown.

Flavor – Ranges from fairly sweet to quite bitter. Bitterness usually comes from a complex interaction between roasted malts and hops.

Mouthfeel – Thick, mouth-coating body with medium-low carbonation. Younger examples can often have some astringency, but this dissipates with some age.

Vitals – 8 – 12% ABV, 50 – 90 IBU

Service Notes:

Serve in a snifter at cellar temp, around 50-55ºF

BJCP DESIGNATION: 20C, Imperial Stout

Overall Impression:

An intensely-flavored, big, dark ale with a wide range of flavor balances and regional interpretations. Roasty-burnt malt with deep dark or dried fruit flavors, and a warming, bittersweet finish. Despite the intense flavors, the components need to meld together to create a complex, harmonious beer, not a hot mess.

Aroma:

Rich and complex, with variable amounts of roasted grains, maltiness, fruity esters, hops, and alcohol. The roasted malt character can take on coffee, dark chocolate, or slightly burnt tones and can be light to moderately strong. The malt aroma can be subtle to rich and barleywine-like. May optionally show a slight specialty malt character (e.g., caramel), but this should only add complexity and not dominate. Fruity esters may be low to moderately strong, and may take on a complex, dark fruit (e.g., plums, prunes, raisins) character. Hop aroma can be very low to quite aggressive, and may contain any hop variety. An alcohol character may be present, but shouldn’t be sharp, hot, or solventy. Aged versions may have a slight vinous or port-like quality, but shouldn’t be sour. The balance can vary with any of the aroma elements taking center stage. Not all possible aromas described need be present; many interpretations are possible. Aging affects the intensity, balance and smoothness of aromatics.

Appearance:

Color may range from very dark reddish-brown to jet black. Opaque. Deep tan to dark brown head. Generally has a well-formed head, although head retention may be low to moderate. High alcohol and viscosity may be visible in “legs” when beer is swirled in a glass.

Flavor:

Rich, deep, complex and frequently quite intense, with variable amounts of roasted malt/grains, maltiness, fruity esters, hop bitterness and flavor, and alcohol. Medium to aggressively high bitterness. Medium-low to high hop flavor (any variety). Moderate to aggressively high roasted malt/grain flavors can suggest bittersweet or unsweetened chocolate, cocoa, and/or strong coffee. A slightly burnt grain, burnt currant or tarry character may be evident. Fruity esters may be low to intense, and can take on a dark fruit character (raisins, plums, or prunes). Malt backbone can be balanced and supportive to rich and barleywine-like, and may optionally show some supporting caramel, bready or toasty flavors. The palate and finish can vary from relatively dry to moderately sweet, usually with some lingering roastiness, hop bitterness and warming character. The balance and intensity of flavors can be affected by aging, with some flavors becoming more subdued over time and some aged, vinous or port-like qualities developing.

Mouthfeel:

Full to very full-bodied and chewy, with a velvety, luscious texture (although the body may decline with long conditioning). Gentle smooth warmth from alcohol should be present and noticeable, but not a primary characteristic; in well-conditioned versions, the alcohol can be deceptive. Should not be syrupy or under-attenuated. Carbonation may be low to moderate, depending on age and conditioning.

Comments:

Traditionally an English style, but it is currently much more popular and widely available in America where it is a craft beer favorite, not a curiosity. Variations exist, with English and American interpretations (predictably, the American versions have more bitterness, roasted character, and finishing hops, while the English varieties reflect a more complex specialty malt character and a more forward ester profile). Not all Imperial Stouts have a clearly ‘English’ or ‘American’ character; anything in between the two variants are allowable as well, which is why it is counter-productive to designate a sub-type when entering a competition. The wide range of allowable characteristics allow for maximum brewer creativity. Judges must be aware of the broad range of the style, and not try to judge all examples as clones of a specific commercial beer.

History:

A style with a long, although not necessarily continuous, heritage. Traces roots to strong English porters brewed for export in the 1700s, and said to have been popular with the Russian Imperial Court. After the Napoleonic wars interrupted trade, these beers were increasingly sold in England. The style eventually all but died out, until being popularly embraced in the modern craft beer era, both in England as a revival and in the United States as a reinterpretation or re-imagination by extending the style with American characteristics.

Characteristic Ingredients:

Well-modified pale malt, with generous quantities of roasted malts and/or grain. May have a complex grain bill using virtually any variety of malt. Any type of hops may be used. American or English ale yeast.

Style Comparison:

Like a black barleywine with every dimension of flavor coming into play. More complex, with a broader range of possible flavors than lower-gravity stouts.

Vital Statistics:

OG: 1.075 – 1.115
FG: 1.018 – 1.030
ABV:  8 – 12%
IBUs:  50 – 90
SRM:  30 – 40

Commercial Examples:

American – Bell’s Expedition Stout, Cigar City Marshal Zhukov’s Imperial Stout, Great Divide Yeti Imperial Stout, North Coast Old Rasputin Imperial Stout, Sierra Nevada Narwhal Imperial Stout; 

English – Courage Imperial Russian Stout, Le Coq Imperial Extra Double Stout, Samuel Smith Imperial Stout

BA DESIGNATION: American-Style Imperial Stout

  • Color: Black
  • Clarity: Opaque
  • Perceived Malt Aroma & Flavor: Extremely rich malty aroma is typical. Extremely rich malty flavor with full sweet malt character is typical. Roasted malt astringency and bitterness can be moderate but should not dominate the overall character.
  • Perceived Hop Aroma & Flavor: Medium-high to high with floral, citrus and/or herbal character.
  • Perceived Bitterness: Medium-high to very high and balanced with rich malt character.
  • Fermentation Characteristics: Fruity esters are high. Diacetyl should not be present.
  • Body: Full.

Original Gravity (°Plato) 1.080-1.100 (19.3-23.7 °Plato)

Apparent Extract/Final Gravity (°Plato) 1.020-1.030 (5.1-7.6 °Plato)

Alcohol by Weight (Volume) 5.5%-9.5% (7.0%-12.0%)

Bitterness (IBU) 50-80

Color SRM (EBC) 40+ (80+ EBC)

BA DESIGNATION: British-Style Imperial Stout

  • Color: Ranging from dark copper typical of some historic examples, to very dark more typical of contemporary examples
  • Clarity: Opaque in darker versions. When clarity is perceivable, chill haze is acceptable at low temperatures.
  • Perceived Malt Aroma & Flavor: Extremely rich malty flavor, often expressed as toffee or caramel, and may be accompanied by very low roasted malt astringency.
  • Perceived Hop Aroma & Flavor: Very low to medium, with floral, citrus or herbal qualities.
  • Perceived Bitterness: Medium, and should not overwhelm the overall balance. The bitterness may be higher in darker versions while maintaining balance with sweet malt.
  • Fermentation Characteristics: High alcohol content is evident. Fruity esters if present are medium to high. Diacetyl should not be present.
  • Body: Full.
  • Additional Notes: The style was also originally called “Russian Imperial Stout.”

Original Gravity (°Plato) 1.080-1.100 (19.3-23.7 °Plato)

Apparent Extract/Final Gravity (°Plato) 1.020-1.030 (5.1-7.6 °Plato)

Alcohol by Weight (Volume) 5.5%-9.5% (7.0%-12.0%)

Bitterness (IBU) 45-65

Color SRM (EBC) 20-35+ (40-70+ EBC)

STYLE COMPARISON:

Similar flavor profile to American or English stouts, but significantly richer and heavier

INGREDIENTS:

  • Pale malt
  • Caramel/Crystal malt
  • Chocolate/roasted malt
  • Roasted barley
  • American or European hops
  • American or English yeast

BREWING PROCESS:

Mash grains in the upper range for a fuller body, or in the mid range for a bit less sweetness. Alternatively, for a stout with less assertive roast character, add the darkest grains at the end of the mash, just before vorlauf. Boil hard for 90 minutes (or more) to develop some caramel/toffee characteristics, then Oxygenate fully (some brewers hit this wort with additional O2 12-16 hours after pitching). Ferment around 68º, raising the temperature after 3-4 days of primary fermentation to ensure full attenuation.

SUGGESTED FOOD PAIRINGS:

AT THE BREWPUB: Dessert – flourless chocolate cake with vanilla bean ice cream
SWANKY DATE NIGHT: Porterhouse with Bayley Hazen crumble

SUGGESTED SPIRIT PAIRINGS:

FROM BF DISTILLING CO: Bourbon, Single Malt Whiskey
ANY: Rye

SUGGESTED MUSIC TO LISTEN TO:

NEW: Tool, 10,000 Days
OLD: Berlioz, Symphonie Fantastique

BEER COCKTAIL RECIPE:

Vermont Maple Rye Flip

INGREDIENTS:

  • 4 ounces BF Imperial Stout
  • 1.5 ounces rye whiskey
  • 1 whole egg (pasteurized if you prefer)
  • .75 ounces Vermont maple syrup

DIRECTIONS:

Pour whiskey, egg, and maple syrup into a cocktail shaker with ice and shake vigorously. Strain into a Teku glass, then top with stout. Shave nutmeg or cinnamon on top.

BLACK FLANNEL BREWING CO. EXAMPLE: Raven Series - Barrel aged Imperial Stout

Brewing Notes:

Coming soon…

Tasting Notes:

Coming soon…