When is temperature important when in primary?

[cannman]

I'm getting ready to brew this season in a new location, new climate, new everything! I've determined I can really only brew in the cold months and therefore plan to wrap my Carboys with a heating wrap that is temperature controlled and monitored from within the ferment.

My question is: when is it important to keep the fermenter heated? Can I remove the heat device from the carboy once gravity stops dropping for 3 or 4 days and let the product sit in the ambient until ready to bottle (no secondary)?

Ambient conditions where the Carboys rest are insulated and may reach as low as 45F at night during winter. Once fermentation is done, is this ok for resting conditions?

Thank you.

 

[Wolfbrau]

You should taste it to check for off flavors and try raising the temperature a few degrees, if possible. If it tastes clean - no diacetyl or acetaldehyde - and there is no activity at a little higher temperature, you're ready to package.

If you can't raise the temp, it may be worthwhile to wait a few more days, even if it's tasting clean. Don't want bottle bombs.

If you aren't ready to package, there won't be any harm in leaving it in primary, even with big temperature swings, since the yeast are, well, done.

 

[Bassman2003]

I think it would be wise to keep to the usual homebrew rules of thumb for the style you are brewing - 2-3 weeks for an ale and 3-4 weeks for a lager. Since you are in reverse to most folks, it might seem like a long time to have the jackets on, but if you are brewing an ale, dropping to 45F will put your yeast to sleep for sure.

 

[brycelarson]

The corner of my basement where I ferment gets quite cold in the winter as well. Ambient temp is around 52-53 at the coldest part of the winter. My standard practice is to ferment until activity has reduced and the beer has started to clarify - then I raise temperature up to about 72 for 2 to 3 days. That's to get the yeast to do it's final cleanup work. I then let it drop to ambient until I'm ready to keg it. For some beers I pull them off immediately - others get a week or two to clarify in the fermenter.

I use a heat belt and that silver bubble wrap.

If you drop to 45 degrees right after the initial fermentation is complete you may not get as clean a beer as you would like. You're basically moving to lagering - which takes a lot of time.

 

[cannman]

If you drop to 45 degrees right after the initial fermentation is complete you may not get as clean a beer as you would like. You're basically moving to lagering - which takes a lot of time.

I thought after the initial fermentation was done (OG not moving any more) all that was really happening was the trub/yeast settling to the bottom thus "clarifying" the beer?

My standard practice is to ferment until activity has reduced and the beer has started to clarify - then I raise temperature up to about 72 for 2 to 3 days. That's to get the yeast to do it's final cleanup work.

Wouldn't encouraging the yeast at this point be counter productive to clarification?

---

I could care less about a cloudy beer...

 

[cannman]

I think it would be wise to keep to the usual homebrew rules of thumb for the style you are brewing - 2-3 weeks for an ale and 3-4 weeks for a lager. Since you are in reverse to most folks, it might seem like a long time to have the jackets on, but if you are brewing an ale, dropping to 45F will put your yeast to sleep for sure.

If we are done with fermentation, what is wrong with having the "yeast go to sleep?"

 

[mrphillips]

No problem at all...as long as you're SURE your fermentation is done! I've had beers drop 4 or 5 points after being stable for a week by softly rolling the bucket/carboy back and forth to wake up the yeast.

BE SURE IT'S DONE FERMENTING! (cue bottle bomb theme music).

 

[cannman]

No problem at all...as long as you're SURE your fermentation is done! I've had beers drop 4 or 5 points after being stable for a week by softly rolling the bucket/carboy back and forth to wake up the yeast.

BE SURE IT'S DONE FERMENTING! (cue bottle bomb theme music).

But how is one ever sure a brew is done fermenting?? I'm already taking gravity readings and comparing them to expectations via recipe and calculation. I'm content with leaving the heat on for as long as necessary and I'm not trying to rush things either.

 

[jtratcliff]

Once yeast have consumed all the ferment able sugars, they will start to work on some of the fermentation by-products that can lead to off flavors.... Commonly called "cleaning up after themselves"

So no need to rush it... Especially if temps are a bit on the low side. Give the wee yeasties time to finish their work.

 

[motobrewer]

http://braukaiser.com/wiki/index.php?title=Understanding_Attenuation

 

[brycelarson]

I thought after the initial fermentation was done (OG not moving any more) all that was really happening was the trub/yeast settling to the bottom thus "clarifying" the beer?

They're also eating Diacetyl and other byproducts of reproduction.

 

[cannman]

http://braukaiser.com/wiki/index.php?title=Understanding_Attenuation

wow what a wonderful resource! A+

 

[Bassman2003]

If we are done with fermentation, what is wrong with having the "yeast go to sleep?"

If you already know the answers, then why ask the question?

You stated that the beer would still have 4-5 gravity points to go when you want to drop the temp to 45F. That does not sound like it is finished with all yeast activity to me. Unless it is a lager it would seem too early to move to a lagering-type temperature.

I keep ales in the primary for two weeks then transfer to keg. This is very accepted practice, so I suggested you keep the jackets on for the standard time.

 

[MindenMan]

I must have misunderstood your post, I thought you were initially asking how many days it is critical to control temperatures; the first three days at least. As far as the temperature staying up, if you are using a high flocking yeast like ESB 1968.
I pitch my yeast around 65*F, and as soon as active fermentation is noticeable, I drop the temp to 55*F until fermentation is done, and raise the temp up to 68*F or so over a few days, cold crash and rack into bottling bucket. My current yeast is Irish Ale 1084, and it ferments very readily at 55*F. I have noticed lately, my beer has a crisper flavor than it used to, and I believe it is a direct result of low fermentation temperatures.

 

[cannman]

I must have misunderstood your post, I thought you were initially asking how many days it is critical to control temperatures;

That is EXACTLY the question

 

[cannman]

If you already know the answers, then why ask the question?

I don't have all the answers but again I'm not a complete newbie to brewing. I have a complex situation coming up this winter so even if I ask a question, it doesn't mean I won't continue independent research . If there was a know all be all, we would need this forum.

 

[cannman]

I keep ales in the primary for two weeks then transfer to keg. This is very accepted practice, so I suggested you keep the jackets on for the standard time.

Perfect. This is exactly what I was looking for. A lot of recipes have a suggested primary time... Looks like the gloves go on per recipe!

 

[Bassman2003]

I'm getting ready to brew this season in a new location, new climate, new everything! I've determined I can really only brew in the cold months and therefore plan to wrap my Carboys with a heating wrap that is temperature controlled and monitored from within the ferment.

My question is: when is it important to keep the fermenter heated? Can I remove the heat device from the carboy once gravity stops dropping for 3 or 4 days and let the product sit in the ambient until ready to bottle (no secondary)?

Ambient conditions where the Carboys rest are insulated and may reach as low as 45F at night during winter. Once fermentation is done, is this ok for resting conditions?

Thank you.

I will try to dissect your questions:

"when is it important to keep the fermenter heated?"

I would say keep the jackets on for the entire length of the "primary fermentation" you decide to use. If you are brewing an English ale that would be roughly 2 weeks at fermentation temps. If you are brewing a Belgian, that might be 3 weeks with a temperature ramp upwards.

Yeast like stable to climbing temperatures. They do not like large drops in temperature. So once you start your jackets, they should stay on for the duration until you move to the keg, bottling or lagering phase.

"Ambient conditions where the Carboys rest are insulated and may reach as low as 45F at night during winter. Once fermentation is done, is this ok for resting conditions?"

Yes, but only if you are considering this to be a "lagering phase". An ale yeast will go to sleep at 45F. Even if you are in a secondary for an ale, you want some yeast activity to finish off the beer. So I would say jackets stay on.

If you are making a lager then it does not matter as the yeast are more comfortable with these temps. But, any yeast will not like ups and downs - 55F during the day and 45F at night. You want constant temps...

 

[cjgenever]

No, once fermentation is complete you need the yeast to stay in suspension to clean up. Even a few degrees drop over night can drop them out of suspension.