How long to let ferment in freezer?

So after 5 batches of stouts/porters with a lot of off flavors, butterscotch smell, I realised I was fermenting way to hot. House stays at around 77 degrees, I was probably fermenting in the 80s... Anyway.

I converted a chest freezer with a thermostat controller to keep my fermentation's in a respectable range, my question is, how long does it need to stay in there? Will a week be long enough, it really only needs to stay within the specified yeast temperature range during active fermentation, right? The most active part of the fermentation is within the first 3 or 4 days, so if it's left in for 7 days and then allowed to warm up to the ambient temperature of my house, will that produce off flavors like what I was experiencing before?

Isn't brewing in Texas summers fun? Nobody else ever asks for help keeping their saisons from overheating. Every successive day is less important than the one before it. You could probably get away with 3-4, but 7 is better. For high-gravity beers, maybe add a day or two.

Yes a week will be enough. I do 3 days then bring them out to room temperature (70).

silvery37 said:

Yes a week will be enough. I do 3 days then bring them out to room temperature (70).

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Room temperature isn't 70, lol. Try 77 - 78.

There in lies my question, if I have it cooled for 7 days then let it room up to 77 degrees (just an average, sometimes it's 75 in here) will that produce any off flavors?

If it's fermented as far as it will go in your freezer, you're safe bringing to room temps, or you could just go the max your controller allows. This will allow the yeast to knock the gravity down those last possible 2-3 points and clean up after itself a little. You'll be well past the yeast multiplication stage, so minimal risk of off-flavors. If you're not bottling, you could skip this step if the flavor is fine. Since you have the freezer, cold-crashing and lagering are other things you can do to smooth out the flavor.

kingwood-kid said:

If it's fermented as far as it will go in your freezer, you're safe bringing to room temps, or you could just go the max your controller allows. This will allow the yeast to knock the gravity down those last possible 2-3 points and clean up after itself a little. You'll be well past the yeast multiplication stage, so minimal risk of off-flavors. If you're not bottling, you could skip this step if the flavor is fine. Since you have the freezer, cold-crashing and lagering are other things you can do to smooth out the flavor.

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Reason I'm asking is I'm wanting to cold crash another batch, so I need to remove what's in the right now before I can do that.

Desp said:

Reason I'm asking is I'm wanting to cold crash another batch, so I need to remove what's in the right now before I can do that.

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If you are done fermenting, why not cold crash them both at the same time?

mredge73 said:

If you are done fermenting, why not cold crash them both at the same time?

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Well what's in there right now is a 1.069 OG pumpkin spice and I doubt it's done completely fermenting, I was going to let it age for about a month or so, I just wasn't sure if after a week of active fermentation if letting it sit at room temp for another couple weeks would cause any off flavors.

It's already been said, but just to reiterate, if your brew has already been going for 7 days you should have absolutely no worries letting it come up to room temp for a couple of weeks of yeast clean up time. Very little, if any, chance of off flavours developing here unless you introduce some contaminant into the beer.

In fact, it seems that the vast majority of off flavours and unwanted compounds, fusels, acetaldehyde, etc. caused from higher temps. are produced mainly in the first 24 to 48 hours from lag through the next couple of days of vigorous fermentation.

Ogri said:

It's already been said, but just to reiterate, if your brew has already been going for 7 days you should have absolutely no worries letting it come up to room temp for a couple of weeks of yeast clean up time. Very little, if any, chance of off flavours developing here unless you introduce some contaminant into the beer.

In fact, it seems that the vast majority of off flavours and unwanted compounds, fusels, acetaldehyde, etc. caused from higher temps. are produced mainly in the first 24 to 48 hours from lag through the next couple of days of vigorous fermentation.

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Thank you, that was the clear and concise answer I was looking for.