Recommendations for brewing an imperial stout at home

Imperial stouts are the bigger sisters of English stouts. Also known as Russian imperial stouts, we can think of them as a fortified version of the British classic. That is, more alcoholic (between 8 and 12% ABV, although some interpretations exceed this range), more intense in flavor and above all fuller, both in richness of nuances and in texture. When brewing these beers at home as homebrewers, we must bear a series of considerations in mind:

• A high original gravity (OG). We need to start from a value between 1.075 and 1.115. This means the wort will be rich in sugars, a necessary condition to achieve a high alcohol content. At the end of fermentation we should have a final gravity (FG) between 1.018 and 1.030 if we have achieved proper attenuation.
• Although imperial stouts are prominently malt-forward beers, some American brewers go overboard with the hops. However, hops should not be present in the aroma, but rather in the bitterness as a counterpoint to balance the sweetness. That’s why it’s not unusual to find imperial stouts with more than 50 and even up to 90 IBUs (bitterness units).
• The malty base of an imperial stout should preferably be pale malt, with a portion of roasted malts that, in addition to providing a deep dark color, will be responsible for giving our beer complexity. We want to obtain a coffee‑like profile with lighter notes of toasted bread, cocoa, or caramel.
• Unlike a Baltic porter (lager), an imperial stout (ale) should emphasize coffee flavors and aromas over chocolate. Likewise, thanks to ale fermentation, an imperial stout can offer fruity aromas (plums, dates, raisins) without these dominating over the roasted character.
• Some brewers age their imperial stouts. This is recommended so that the stronger versions have time to round out and settle their full sensory profile. Extended aging can impart a certain oxidation to an imperial stout, which translates into a highly prized wine-like character.
• As for the yeast, we opt for English or American top-fermenting (ale) strains, as these are the ones most commonly used by professional brewers for their imperial stouts.

Some brewers choose to add other grains such as wheat, oats, or roasted barley to create different sensations, but that’s up to individual preference. Remember that a good imperial stout is much more than coffee and alcohol. So combine different specialty malts with an estery yeast to add complexity. And if you want to experiment further, you can age the beer in barrels or with wood chips for a few months. Ready to brew your first homemade imperial stout?