US-05 temperature dropped too low

[jclavel]

I brewed a batch of dead guy and pitched US-05 for 7 days at 65F. On day 6 the temperature outside dropped to the mid forties and because of that the freezer that I use as a fermentation chamber dropped to below the set point of 65F. When I opened the freezer yesterday morning, the temp was 58 and there was a cheesy yeasty foam inside and coming out of the airlock. Is this a problem? What is it?

 

[KraphtBier]

Are those temperatures ambient or actual? If you are measuring ambient the odds are good that the temp in the fermenter is higher than the ambient temperature by at least a few degrees.

It sounds like you are experiencing blow off. Clean out your airlock and replace it. Make sure to sanitize the outside of the carboy if any gunk spilled out on to it. Use the search function and look up "blow-off tube" and you shouldn't have this problem ever again.

 

[BWN]

I think you could get by with 58 for that yeast anyways.

 

[jclavel]

Good to hear. The temperature I'm speaking of is ambient, and I caught it after about a day. I any event, one of the buckets was racked prior to raising temperature to 68ish, the other was not. I'll report back regarding the difference in flavor profiles found. I'm not sure about blow-off being an issue, but it certainly could be. This I the first time I've fermented sub 65, so population growth may have been slower, thus fooling me regarding timing. Normally, at 69F blowoff rates scream at about 36 hours; which was not the case with this batch.

 

[LAbrewer]

a temp drop like that after 6 days of normal fermentation is not going to matter much. check the gravity.

 

[masskrug]

I had mine in the high 50's for about a week and it stalled out. I gently stirred the cake, warmed up the fermenter slowly over a few days and it finished out just fine.