Brewing a Dry Irish Stout with S-04. Pitched 4:00 PM yesterday at 58°F. Two inch rise in the krausen this morning at 62.4°F in one hour. Swamp cooler, wet towel, and fan going to hold the temperature. Temperature is currently at 62.1°. Krausen started coming through the air lock earlier this evening. Refilled the air lock with Star San solution. Shouldn’t have a problem with the air lock blowing off. No hop debris or grain bits to plug it up. I’ll replace the air lock tomorrow when the fermentation slows. Never had a krausen that was just light foam and increased in volume this fast with any other yeast.
My experience with 04 is it’s vigorous but still needed time to finish. I would normally let it warm up after a couple to try and keep the fermentation going.
Krausen is no longer being pushed through the air lock. New air lock this morning and clean the beer from the top of the carboy to prevent mold growth.
Thermometer I was using went wonky. Touching it made it go wild. Thermoworks Dot shows a temperature of 64°. Wanted to avoid elevated levels of esters since this is a stout but I seem to get a little banana through the air lock. Hope my nose is wrong. May bring it up to 65° tomorrow.
What you smell from the air lock usually doesn’t reflect the beer thank goodness. Fermenting cool will definitely give you a clean finish. I personally like the taste I get from the warmer fermentation. I don’t ferment Belgian warm just upper 60s. Never got banana.
I’m hoping that will be the case with this one. If not my back up plan is to drink this stout with an addition of cold brewed coffee with each pour.
Just an update on the activity of S04. After 12 hours the krausen had dropped. Replaced the airlock with a clean one after cleaning the top of the carboy of the krausen that had pushed through. 12 hours later the temperature of the beer dropped from 63.5°F to 61.9°F. Turned on the temp controlled aquarium heater to warm the water bath to 65°. Raised the temperature 1° each day until the water bath was 68°. Holding at that temperature until it is ready to bottle. Stout has been in the fermentor for 9 days now. Star San in air lock still shows some bubbles. Fermentation may be slowly progressing or the bubbles are just caused by CO2 being released from solution.
On the 4th day after active fermentation had started the SG was 1.014. Will check the SG again today.