Homebrew Beer Blog

More O2 stuff. I’ve got all kinds of stuff scribbled on scrap pieces, so if anything, I’ll get it all recorded somewhere. I’ll indicate ethyl acetate as time goes on. I’ll let them age a bit and pass them around for some opinions.

Unless noted, all batches are about 1.048 and pitch about 1.5 million cells/ml/P. Oxygen uses a 0.5 micron stone on the end of a tube and stirred around, pitched and fermented at 48-50 degrees.

#1 = Starter w/ 4L of fresh wort and two tubes of 833. Saturated w/ pure O2. Batch was saturated with pure 02 (Seems mildly nail polish and acrid tasting)

#2 = Stirplate canned starter of 2 tubes of 830 w/ nutrients. Aerated w/ aquarium pump. (Smells of EA and is acrid)

#3 & #4 are 3/4 gal test batches pitched from a tube giving same approximate pitching rate.

#3 = Fresh test extract batch w/ nutrients. 833. Oxygenated to 10 ppm. Pitched at 57 degrees, fermented at 48-50. (Smells fruity, may be acetaldehyde. Seems to taste clean)

#4 = Fresh test extract batch w/ nutrient 833. Oxygenated to saturation. Pitched at 57 degrees, fermented at 48-50. (Same fruitiness, but less so. Seems to taste acrid.)

#5 & #6 I screwed up. The gravity was only 1.025, instead of 1.048 on 3/4 gal test batches If I figured this right, that would mean I pitched about 3 million cells/ml/P. Oh well. We’ll still see if anything interesting happens.

#5 Starter of 820 stir plate w/ fresh extract & nutrient. AG test wort oxygenated to 10.3 ppm.

#6 Starter of 820 stir plate w/ fresh extract & nutrient. AG test wort oxygenated to saturation.’

#7 Not really an experiment, but an IPA w/ measured 10.x ppm O2. Maybe I’ll notice a change.