Imperial Porter style beers have a deep brown colour an ABV between 4.8% and 6.5% and a high bitterness
Imperial Porter characteristics
Imperial Porter or American Porter is a more aggresive version of pre-prohibition Porters or English Porters. It has a dark brown appearance and strong dark malt aromas, with some burnt character and malt additions—chocolate, coffee, etc.— and some hop, even dry hopped. Flavor is malty, with some roasted character, and medium to high bitterness and finish is from dry to sweet. It is more bitter and alcoholic than English Porters, and less strong than American Stouts.
Imperial Porter or American Porter has its origin in the reciped brewed by Fitz Matag as the Anchor Brewing American Porter in 1972. This beer was inspired by a recipe from the pre-prohibition era, using bottom fermenting yeast—altough the very same beer is now brewed with top fermenting yeast. This style became popular in the 1980s, incorporating top fermenting and new American hops.
A Brewery With A Gun interview
Amager (Denmark), 01/05/2018
Henrik Papsø (Amager Bryghus), “If you go to a bar, you see a lot of breweries just name their beers in behalf of the style. And it’s just so boring. Right now I’m so happy that so many brewers are so lazy, because it leaves more room to us.”