Temperature fluctuations question

[trailrunner13]

Ok, so chalk this up to a noob question, but I haven't been able to find an answer to this yet.

Does temperature fluctuation retard or affect fermentation? This is my first brew. 5 galling fermentation bucket. US-05 yeast. After I pitched it, I put it in my powder room bath and noticed activity pretty quickly. The temp on the bucket was 70, sometimes 68. This was Friday night. Today I put it in the linen closet in the same bathroom and the temp is between 64 and 66 and my airlock has slowed considerably.

Is this just a coincidence based upon timeframe or is fluctuating temperature detrimental to the fermentation process?

I know that fermentation isn't complete, and I fully plan on waiting at least 10 days before I start checking FG, followed by dry hopping 5-7 days in the primary before I cold crash for a couple of days.

I'm just wondering, for future batches, if I need to keep fermentation temperature constant?

 

[eadavis80]

Constant is ideal, but for most of us - especially newer brewers, it's not really possible. Just try to keep the yeast in the ideal range and preferably, on the low end of it, whenever possible. Most of the bad effects from bad fermentation temp, in my experience, stem from too high a ferm temp. IT might take a while to get the active fermentation going while wort is cool, but home brewing teaches patience and attention to detail, if nothing else.

 

[Ski12568]

In the beginning when the yeast are most active, they will create a bit of heat from all the work they are doing. Anywhere from 4-8 degrees F, maybe more. It should settle down now that the yeast fell.