Surly Sunday Brewday 11/6/11

Along with pitching yeast to two batches of cider and brewing a mini-batch of hefeweizen imperial stout, we brewed a 2.5 gallon batch of stout to which we intend to add coffee. Seeing as roasted grains, particularly roasted unmalted barley, are the main flavor in any stout worthy of the name, adding the right amount of roasted barley is crucial. We used our previous experience brewing dark beers to hone in what we hope will be an ideal percentage of roasted grains for an imperial stout of appropriate intensity. We're also adding some Belgian dark sugar syrup we had on hand, which should add a caramel/raisin complexity and a touch of dryness.

Batch Size: 2.5 gal

Boil Volume: 3.5 gal

Calculated OG: 1.089

Estimated FG: 1.020

Estimated ABV: 9.1

Calculated IBUs (Tinseth): 49

Pitching Temperature: 65F

Yeast: Wyeast American Ale 1056

Starter: none

Fermentation vessel: Bucket

Malts Mashed		Amount	%
Roast Barley		1.1	17%
Chocolate		0.7	11%

Other Fermentables		Amount	%
DME		4	63%
Candi Sugar (dark)		0.5	8%

Hops/Additions		Amount	Time	AA%	IBU's
Horizon		0.8	60	11.9%	49.27

I've had some coffee beers that I liked, and some that I didn't. Based on my experience with espresso pulled directly into beer, I came to the conclusion that not everything in coffee is complementary to beer. Many of the coffee acids and solids that abound in espresso, for example, are quite unpleasant in beer. How full-bodied the coffee is has no consequence, because it will be overwhelmed by how full-bodied the beer is. What is really desired in a coffee stout is just the aromatic compounds from the beans. I therefore decided to cold brew the coffee and add it to the beer at bottling, to limit the quantity of solids and acids in the beer.

We tasted 5 different coffees from Peet's Coffee and Tea: a washed Ethiopian, a Kenyan (also washed), a Mocha-Java blend, Peet's Fair Trade Blend, and a Sulawesi. I cold-brewed .1 lbs of each coffee with 12 oz of water at ~70F for a little over 24 hours, then poured them through a paper filter.

Coffee cold-brewing for the taste test

We chilled and tasted the coffees, as well as adding them to a sample of the stout from the fermenter. We found that the Arabian Mocha-Java provided the perfect complement to the roasted barley of the stout, bringing out a more intense chocolate flavor than was present in either the coffee or the beer alone. Sulawesi ran a close second; I would definitely consider using it in a future beer.

I brewed .25 lbs of Mocha Java—ground medium-fine—in a quart of water at ~70F for a little under 24 hours. I left much of the water behind with the grounds in hopes of a cleaner flavor, and faster filtering since I had work that day, so we ended up with about 17 oz of concentrated cold-brew, or about 5% of the total volume. This level of coffee is distinct, but not overpowering. Chocolate and earthy notes dominate the aroma, but the beer finishes malty with enough bitterness for balance. Very full-bodied with a light effervescence. Delicious.

Bottled on 12/3/11 to 2 vol. of C02 and added 17 oz of concentrated, cold-brewed Arabian Mocha Java.