How Am I Affecting the Yeast in My Swamp Cooler When...

[RLinNH]

When I dump the temp 2-3 degrees? Such as this particular fermentation I have going on right now. It's a Nottingham yeast in a 1.057 beer. I want to ferment at 65 degrees. Nut Brown Ale. Pitched on Sunday evening with the water at 63 degrees. Checked it out Monday morning at 0500, water at 64 degrees, slow bubbles in the overflow bucket. Monday night, good activity, water still at 64 degrees. Came home today, rapid fermentation, but at 67.4 degrees. Threw in 2, 1 gallon frozen waters, brought Water temp back down to 63 degrees. Granted, the middle of the carboys are probably at 66ish degrees, but here's my question. How am I negatively affecting my fermentation by doing this, if any? I have been cooling like this for many years, and lately I haven't been getting the attenuation that I would like. With this beer, I'll take it out of the swamp cooler once fermentation activity has slowed to raise the temp to try and get better attenuation.

 

[rlmiller10]

When I dump the temp 2-3 degrees? Such as this particular fermentation I have going on right now. It's a Nottingham yeast in a 1.057 beer. I want to ferment at 65 degrees. Nut Brown Ale. Pitched on Sunday evening with the water at 63 degrees. Checked it out Monday morning at 0500, water at 64 degrees, slow bubbles in the overflow bucket. Monday night, good activity, water still at 64 degrees. Came home today, rapid fermentation, but at 67.4 degrees. Threw in 2, 1 gallon frozen waters, brought Water temp back down to 63 degrees. Granted, the middle of the carboys are probably at 66ish degrees, but here's my question. How am I negatively affecting my fermentation by doing this, if any? I have been cooling like this for many years, and lately I haven't been getting the attenuation that I would like. With this beer, I'll take it out of the swamp cooler once fermentation activity has slowed to raise the temp to try and get better attenuation.

Constant temp would be better but a three degree drop should not shock your yeast or anything. Everything I have read says Nottingham can ferment down to low 60s and even upper 50s so I think you will be fine, right in the sweet spot.

Your fermentation will probably slow a bit. It could be from both cooling temp and getting past peak fermentation.

Shorter answer, no negative affects.