Does frequently adjusting ferm temp effect the beer in the end?

[expatriateNZ]

I've found that ambient conditions where I live keep my ale fermentation a few degrees below the minimum recommended temperature range for the yeast without any temperature controls. I've been struggling with keeping it in range when I'm absent (work, sleep), and have let it fall below range a few times. I've been immediately heating it up to top of range, and am wondering if making a habit of this is going to screw up the beer.

Obviously I need to improve my methods, but am curious for the future: should one be wary of making too frequent (and/or large) changes to the temp during fermentation?

 

[GilSwillBasementBrews]

You generally want to keep fluctuations to a minimum. You could try using a different yeast as many of them have varying optimum temperature ranges to find one that works. Also keep in mind that actively fermenting yeast generate heat so if your ambient temp is near the bottom of the range during fermentation the heat generated will be slightly higher than ambient which could be pushing you into range the yeast prefer.

 

[ludomonster]

A lot of people are successful with chilling with water and ice bottles. Swings within the yeast's recommended temperature ranges are OK. Some estery yeasts produce different esters at different ranges withing the recommended range. So, take that into consideration.

 

[billl]

You should definitely not purposely keep changing temps from something like 60 up to 72.

Besides, as pointed about above, the fermenter temp will be a couple degrees over ambient temp. If you want to be at 62 and the room is 60, that is just about perfect.

 

[stratslinger]

Actually, folks are understating the temperature difference between fermenter and ambient - during active ferment, that difference is typically 5-10 degrees. Are you judging your ferment temps based on ambient or based on a stick on thermometer strip? And if one of those strips, have you checked it against a known good thermometer for accuracy?

You may not have a problem at all!

 

[dstranger99]

On my last 2 batches I've been real anal with the ferm temps. Been keeping the bucket in a cooler with 30% water and a water jug that's swapped out for a fresh one daily, I was able to keep my irish stout at 69-71 degrees quite consistent until it finished........

 

[J187]

Increasing the thermal mass of your bucket will not only give you an easier method for active control - frozen water bottles, aquarium heater etc, but it also helps a great deal with consistency as well. Ambient temp changes will effect your fermenting wort much more slowly if you increase the thermal mass. I use a cheapo rubbermaid bin, $4 from Target, that my bucket sits in the middle of and I fill with a few gallons of water. I like the size of the rectangular bin because it allows me to add enough water to effect temp change, yet not have the water come up high enough on my bucket to either A. Obscure my view of my fermometer or B. contact the fermometer.

 

[expatriateNZ]

Thanks to everyone for the suggestions and insight. I've gotten this one stabilized now with a comforter and a small heater. It seems to be doing ok. I'm only going to have issues keeping the temps up, because this town stays in the lager ranges year round. I guess I should be brewing lagers.

 

[sww35]

Increasing the thermal mass of your bucket will not give you an easier method for active control - frozen water bottles, aquarium heater etc, but it also helps a great deal with consistency as well. Ambient temp changes will effect your fermenting wort much more slowly if you increase the thermal mass. I use a cheapo rubbermaid bin, $4 from Target, that my bucket sits in the middle of and I fill with a few gallons of water. I like the size of the rectangular bin because it allows me to add enough water to effect temp change, yet not have the water come up high enough on my bucket to either A. Obscure my view of my fermometer or B. contact the fermometer.

This is also what I do. Not to mention, I feel more secure with the bin just in case I have an issue with blow off. I also have a fan blowing over this setup kind of like a swamp cooler. Because this setup is in my basement, room temp is prolly sitting at 69 degrees so the addition of water into the bin and the fan blowing, I have no real need to add ice bottles and I keep a pretty consistent temp during the whole process. However, I am very inexperienced in the entire brewing process.