The black color comes from cold-steeping dehusked roasted grains. The original recipe uses Perla Negra. I substituted for Weyermann Carafa Special I since it matches in °L. As far as I know, both malts were processed in a similar way: dehusked roasted barley.
I also tweeked the amounts to round numbers in metric, easier to remember on your way to the LHBS. I used 0.5kg of the Carafa Special I instead of the 1 lbs of Perla Negra. I also used 5.5kg of Weyermann Pale malt instead of the 12.5lbs of 2-row. Slightly less base malt, slightly more roasted malt. Why worry?
I created a big starter from a wy1056 smackpack. The fermentation was then kept at 18°C by fermenting in my fridge controlled by my TFBrew software.. This gave a very clean fermentation. The fermentation was vigorous, huge krauzen.
The result is a very nice beer, crisp and refreshing. It’s not an IPA though, at least not what I got. There hop aroma and is hiding behind the aroma from the roasted grains.
The original recipe states that you should expect an OG of 1.075. I didn’t get that. I wonder if there is a mistake in the OG calculations. Using 12.5lbs of 2-row with grain extract potential of 80% and efficiency of 75% you get:
75%* (46 * 80% * 12.5lbs/5gallons) = 69 points or 1.069 expected OG instead of 1.075.
I usually aim for 21-22 liters (5.5 gallons) to account for trub loss etc (further lowering the OG) . Slightly less basemalt and slightly more water gave me an OG of 1.060 or so. Why worry?
Below are some pictures I took during the process of brewing this beer on my electric BIAB system.