"Secondary" Fermentation/Conditioning Temperature

[3 Dawg Night]

I can't believe that I would be the first to ask about this, but I can't quite find the answer to my question.

Background: I'm using a 7-gal Fermonster for primary, and I leave my beer in there for three weeks before bottle conditioning for three weeks. I used a mini-fridge with a temperature controller to ferment at 67-68 degF for about five days (until fermentation activity shows signs of slowing), then I raise the temperature gradually over ~48 hours to the lower of 75 degF or the top end of the yeast's ideal range. I haven't tried cold-crashing yet, but I probably will in the next few batches.

Question: At what temperature should I hold my fermentor for that secondary/conditioning phase (i.e., weeks two and three)? Should I just leave it at 75 degF until I cold crash, or once fermentation is really done (no airlock activity & krausen fully fallen), should I lower the temperature back down to my initial fermentation temperature?

I have a feeling that the answer is that I'm way overthinking it, it doesn't really matter, and RDWHAHB.

 

[VikeMan]

I would say there's usually no reason to increase the temperature to 75F in the first place for most yeast strains/styles.

As far as lowering the temperature from wherever you are to cold crash temperatures... as long as fermentation is complete and there are no off flavors, go ahead and crash. Assuming you aren't doing very small batches, IMO you can't really crash too fast with typical cooling setups...the beer has a lot of thermal mass.

But if you are cold crashing, I'd recommend making sure you have a way to prevent sucking air into the fermenter.

 

[3 Dawg Night]

I would say there's usually no reason to increase the temperature to 75F in the first place for most yeast strains/styles.

I've read in several places that it's a good idea to raise the temperature toward the end of fermentation, to help encourage the yeast to finish up. Theoretically, higher temperatures late in fermentation won't cause off-flavors as in early fermentation.

I get the impression that your recommendation would be to set the initial fermentation temperature and leave it for three weeks (or until SG stabilizes and off-flavors are not present).

 

[VikeMan]

I've read in several places that it's a good idea to raise the temperature toward the end of fermentation, to help encourage the yeast to finish up. Theoretically, higher temperatures late in fermentation won't cause off-flavors as in early fermentation.

If you are in a hurry, raising the temperature toward the end of fermentation can help it finish faster, but in a healthy fermentation, it should rarely be necessary. One exception would be a diacetyl rest when using a strain prone to producing excess diacetyl. But even then, more time at the original fermentation temp usually does the trick. You mentioned that you normally leave the beer in your fermenter for three weeks. For most beers, that should be more than long enough, without having to raise the temp.

I get the impression that your recommendation would be to set the initial fermentation temperature and leave it for three weeks (or until SG stabilizes and off-flavors are not present).

Yes, the stable gravity and lack of off flavors are key. But I wouldn't say you should always set a temperature and keep it there until the end. Sometimes it's beneficial to start at a temp lower than your target fermentation temp and ramp up to the target temp over a couple days, to limit fusel production and ester production downstream. (That's a little different from raising the temp at the end to expedite finishing.)

 

[3 Dawg Night]

Thanks for the info, @VikeMan! I am very much still learning, and I'm trying new things to see what works best with my setup. Playing around with temperature was my tweak this time. I'm trying to make myself not hurry, and I want to simplify things as much as possible, so I'll probably go back to setting my initial temp. leave it there for three weeks, bottling, then drinking after another three weeks.

I read the following somewhere (probably here on HBT): "Do what is needed to brew great beer, and not much more. Set your system up to be as complex as necessary, but no more." I'm trying to make that my homebrewing mantra!

 

[Kickass]

I read the following somewhere (probably here on HBT): "Do what is needed to brew great beer, and not much more. Set your system up to be as complex as necessary, but no more." I'm trying to make that my homebrewing mantra!

I subscribe to this also. Just a thought, but... you’re likely accomplishing very little (with low to medium gravity wort) with an extra two weeks of conditioning, especially with temp controlled fermentation. I rarely ferment an ale beyond 7 days. Just something to consider.

 

[3 Dawg Night]

I subscribe to this also. Just a thought, but... you’re likely accomplishing very little (with low to medium gravity wort) with an extra two weeks of conditioning, especially with temp controlled fermentation. I rarely ferment an ale beyond 7 days. Just something to consider.

It's really the simplicity thing. I'm the only beer drinker in my house, so I don't need to brew more often than every 6-7 weeks. I'd rather just leave it in the fermentor for three weeks than mess with repeated gravity samples. I have no doubt that it's finished before three weeks, but I KNOW that it's finished after three weeks.

 

[Kickass]

I totally get it. If it satisfies the requirements, no need changing.

 

[3 Dawg Night]

I totally get it. If it satisfies the requirements, no need changing.

At least, that's what I keep trying to tell myself. I'm an engineer by trade, so it's REALLY hard not to keep chasing gadgets!

 

[jclark248]

I can't believe that I would be the first to ask about this, but I can't quite find the answer to my question.

Background: I'm using a 7-gal Fermonster for primary, and I leave my beer in there for three weeks before bottle conditioning for three weeks. I used a mini-fridge with a temperature controller to ferment at 67-68 degF for about five days (until fermentation activity shows signs of slowing), then I raise the temperature gradually over ~48 hours to the lower of 75 degF or the top end of the yeast's ideal range. I haven't tried cold-crashing yet, but I probably will in the next few batches.

Question: At what temperature should I hold my fermentor for that secondary/conditioning phase (i.e., weeks two and three)? Should I just leave it at 75 degF until I cold crash, or once fermentation is really done (no airlock activity & krausen fully fallen), should I lower the temperature back down to my initial fermentation temperature?

I have a feeling that the answer is that I'm way overthinking it, it doesn't really matter, and RDWHAHB.

 

[jclark248]

You’re not over thinking it. You can develop certain yeast profiles in temperature control. Rule of thumb is 5days lower end of yeast temp, 5 days mid range and 3 days at top of temp range (good time to add most dry hopping) then cold crash for 2-3 days at dispensing temp. Enjoy