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Sudden temp drop in fermentor

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Rave

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Sep 12, 2010
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I'm in the third day of fermenting a lager, which I do by using an old freezer chest. I started fermenting at 55 degrees in which everything was going good and there was obvious activity in the airlock. Today I checked in the the brew and found that the temp had dropped to about 35 degrees. It had been like this for about 8 hours and the airlock had stopped. I performed some emergency procedures and got the temp back to 55 degrees. The airlock is back to its old bubbly self. My question is what kind of flavor impact is the sudden temp drop going to leave in the brew (if any)? I made a mildly hoppy Lager (Summer weather beer)and used White Labs American Lager yeast. Any opinions will be appreciated.
 
This isn't a good habit to get into of course, but I imagine it will be fine. The only real risk I could imagine is temperature-shock metabolites, but if you can't taste an off flavor then you're good. The good odds are that you'll never notice.
 
Thanks for the reply. It's been close to twelve hours since I got the temp back up and everything seems to be alright.
 
This isn't a good habit to get into of course, but I imagine it will be fine. The only real risk I could imagine is temperature-shock metabolites, but if you can't taste an off flavor then you're good. The good odds are that you'll never notice.

I agree. Not a great practice, but I'll add that you would have been much worse off if the temperature had been an increase rather than a decrease. You don't want to see a mistake like that at such a critical point of fermentation, but you should be fine. You pitched at a pretty good temperature for a lager, and those lager yeast are sill able to perform at cold temperatures, so I do not think you shocked them too badly. Just give it plenty of time at fermentation temperature to clean up any problems you may have caused before you crash it back down to lager. I've bottle conditioned a lager on a garage floor in the middle of winter, and even at near freezing temperatures, those yeast were happy to carbonate my beer, so I am sure they were still working during your 8 hour dip.

Joe
 
I've bottle conditioned a lager on a garage floor in the middle of winter, and even at near freezing temperatures, those yeast were happy to carbonate my beer

Joe

This leads me to question about bottle conditioning lagers. Did you add more yeast at bottling time or did the original yeast to the job? I'm sure the answer is in here somewhere, but if you can enlighten me a bit I'd appreciate it.
 
That is a good question. When I did it, I did not know the answer either but I took my chances and did not add more yeast before I bottled. I can even take it one step further. I ferment using a minifridge and ferm wrap. It was easy to hold my fermentation temp at 49/50 degrees for 4 weeks. It was my plan to just turn off the ferm wrap, and let the beer slowly crash to fridge temperatures for the next month or so. I took it out after four weeks of lagering at what I thought were fridge temps, and the top half of the carboy was completely frozen.

I cursed a bit, let it thaw out, and then went on with bottling as usual. To my surprise, carbonation was not a problem, and to make this as clear as possible, I never added more yeast after the initial pitch. Also, I was using WLP833.

Joe
 

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