Oh, and yes, I did throw the dregs of this yeast on top of a gallon of Russian Imperial Stout, and I do not recommend it. I can understand why there are no sour stouts around. The combination of lots o hops, sour and roasty notes is not good. Blech.I've had one that I can remember, a commercial Belgian Stout that was definitely sour. I agree, it was not pleasant.