The two attached photos are of imperial stout a friend and I brewed, 15 hours and 22 hours after pitching.
There was about ~11 gallons/41 liters of 1.089 wort in a 15.5 gallon/58 liter cut off SS Hoff-Stevens barrel (opening is 13″/33 cm diameter). I pitched 10 fl. oz. (300 ml) of thick, top-cropped WhiteLabs WLP103 London Ale Yeast, which makes a thick yeasty head.
I aerated the chilled wort (66F/19C) when transferring it to plastic carboys for transporting it home by running it down the inside of the carboys, then again by dumping it forcefully into the fermenter, then again five hours later by bubbling filtered air through it for 30 minutes (coarse bubbler). I want this baby to finish completely!
I hadn’t counted on this vigorous a ferment, though. I don’t normally ferment uncovered, but at 14 hours it had pushed the lid off. I covered it with 18″/49cm wide plastic wrap with the sides stuck down with sterilant solution, and it pushed this up in a bubble in a matter of minutes, then after an hour, pushed it off.
I cleaned up, skimmed, and left it uncovered. The first photo is a half hour later or so. The twisting, braided, arching tendrils looked alive. At this point the foam was light with no particular yeast.
I shut off the heat vent and closed the door (in a small bathroom) to keep out air borne contaminants (also stopped using that toilet) and to try to keep it cooler. The ambient temperature had been 68F/20C and the beer temperature just slightly higher.
During the day, the foamy head kept pushing up over the top. I had to skim it every hour, then more often. It began to get somewhat denser with yeast, and towards 24 hours the thick foam I dumped in the sink shook like jelly or mousse. I tried simply beating it down (but not into the fermenting beer itself) but that would only buy me about 15 minutes.
Finally, at bedtime, about hours 30 after pitching, I skimmed it down to about an inch of head, then covered it with plastic wrap with the narrower overlap on the side of the keg over the sink (it was sitting on the sink counter). I figured that would be where it would pull off and act as a safety valve.
I got up this morning expecting to see foam pushing out from under the door, but happily, the fermentation had abated enough that it had pulled off the plastic only at the side. About a cup of thick yeast (felt like thick, wet mud) had collected on the towel beside the barrel, and the beer had drained out of the yeast into the sink.
The temperature in the room had dropped overnight 60 60F/15C, but the beer was still 68.7F/20.4C) I think this might have helped control the rate of fermentation, but more likely it was simply slowing from having fermented much/most of the fermentables.
I’ve attached a Recipator file of the recipe for those who are interested. Of some interest, I think, is that I used 21% brown malt and 2 lbs of Lyle’s Golden Syrup, which has 1.6 lbs solid invert sugar (glucose).
I’m looking forward to tasting this when it’s finished. It smells fantastic, with notes of dark malt, licorice, molasses, cocoa, toasted oak, all kinds of dark notes.