I have fluctuating fermentation temps, but they are within ideal range. Problem?

[BitterSweetBrews]

Quick question.

My fermentation fridge is full. I am fermenting 8 gallons of a Milk Stout with some harvested / started S-04 yeast in a closet in the corner of my basement. It has been going for 2 weeks today. With outside temps this past couple weeks ranging from 10 - 35 degrees F, the temperature in the closet has fluctuated too. I have seen it anywhere from 60 - 68 degrees F.

The SG has gone down steadily from 1.060 to where it is now pretty much finished at 1.020, about what I expected. I do occasionally see a bubble in the airlock (good seal). It tastes good.

Would anyone have expected any issues from the temp fluctuations, given that they are within the ideal fermentation range of S-04?

Just curious. I am going to RDWHAHB because it is going to be a good beer.

 

[kh54s10]

Since that is a good temperature range, and the wort will fluctuate much more slowly, I don't think you will have any problems. But remember that fermentation creates heat so if you ambient temperature is 68 the wort temperature could go higher, near 78 degrees.

It is best to keep the temperature as stable as possible unless you are changing it on purpose, like raising the temperature at the end of the fermentation to help it finish.

If you put the fermenter in a large container of water that would give more mass for ambient to have to change and the temperature will be more stable. You can also add hot water bottles or ice bottles to control the temperature of the fermenting wort.

 

[Homercidal]

I'd say you are in the range where the yeast won't really change a lot. It may be a godo idea to use a swamp cooler to minimize the fluctuation even more. The mass of the water will kind of insulate the beer and help it remain steadier. I wouldn't expect any real off flavor from those temps, though.

 

[RopesByEDK]

I was wondering this myself.

My fermenting carboy gets stored in a second bedroom. And it stays within the temp range. But I am more worried about the summertime.

I will most likely move my fermentation spot to the basement. Which should keep my temp stable.

I did receive a heating blanket and plug in thermostat for Christmas, but really haven't seen a need to use it as my temps are holding good. (For ales at least).

I'm new to this so I anticipate that I won't be getting more complex with things for a while. However, I want to soak up as much knowledge as I possibly can now.

Out of curiosity, does the yeast govern the temperature you want to ferment at? Or is it more of a combination of brew type + yeast?

 

[SmokeyMcBong]

The yeast will have a specific temp range listed in its specs. I usually try to stay on the low end of the spec...

 

[JONNYROTTEN]

What is the recipe where you start at 1.060 and end at 1.020? Something seems off there. I would think you should have a much lower FG.
I have an 1.060 going now and target FG is 1.010

 

[BitterSweetBrews]

The expected final was Beersmithed out at 1.015. I'm not stressing about 1.020. Beersmith said my SG was going to be 1.057 and it was 1.060, 3 points higher. So I am only off 2 points on a sliding scale. Could be my hydrometer, but I checked it with 2 and they are the same.

I am going to move it out to a warmer area for a day or two to finish before cold crashing, maybe it will get down a few more points. But I doubt it, since it has been 16 days since pitching.

 

[Homercidal]

Just so you understand, moving your beer to a warmer location may cause bubbles to rise. Not necessarily due to further fermentation (although it might be from that) but from the fact that colder beer holds onto CO2 better, so moving and warming may cause some of that CO2 to escape. So you might see some bubbles.

 

[BitterSweetBrews]

Just so you understand, moving your beer to a warmer location may cause bubbles to rise. Not necessarily due to further fermentation (although it might be from that) but from the fact that colder beer holds onto CO2 better, so moving and warming may cause some of that CO2 to escape. So you might see some bubbles.

I won't watch for bubbles, just want to excite the yeasties a bit.

My research has found that CO2 doesn't necessarily escape at higher temps if it isn't under pressure. That's why when your plugging numbers into a carbonation calculator it asks for the lowest temp the beer was at during fermentation, because it already has that much CO2 in it.