Questions regarding fermentation temps.

[McDingleberry]

So, I brewed my second batch on Sunday, and it started bubbling away within 12 hours. It's the IPA kit from Northern Brewer. Anyway, I have been watching the temperature of the bucket very closely, as I want to try to keep a steady temperature. Yesterday morning the bucket was in my hallway that stays about 62 degrees (I am keeping a digital thermometer within a foot of the bucket to measure ambient) and the bucket was reading 64. Then, in the afternoon, the bubbles in the blow-off really got pretty fast and the bucket went up to 66 and ambient was still 62. When I was about to go to bed the bucket looked like it was on it's way to 68, so I moved it to an unheated bedroom to keep things in check.

I woke up and the bucket is at about 64-65 and the ambient is 55 so it is about 10 degrees over ambient, so I'm glad I moved it. My question is, how long should I be careful about this? I have heard that it is only really important while the majority of the fermentation is taking place, maybe the first week or so. I plan on leaving the beer in the primary for at least 3 weeks, but I think by the end of that time, warmer weather will be here and my house may be around 70 degrees. If the specific gravity is just about stable after 2 weeks, does the temperature really matter at all? I plan on building a ferm chamber in my spare bedroom, so hopefully this will be the only batch that I need to worry about.

 

[FensterBos]

Well, you definitely want to control the temperature fluctuation right now. Going from 62 to 68 back to 64 isn't the best for the yeast; generally you want to limit temperature change to one degree a day. But, I think you were smart for moving the bucket to the cooler part of the house; you probably prevented the beer from getting too hot.
Check the recommended fermentation temperature on the yeast packet; as long as you stay within the recommended range during initial/primary fermentation you'll be fine. It is recommended to bottle condition at warmer temperatures to ensure that carbonation occurs accurately.
What yeast are you using?

 

[FensterBos]

Oh yeah, RDWAHAB

 

[McDingleberry]

Just to clarify, the bucket temp was never at 62, I pitched at 64 and it stayed 64 until yesterday afternoon when I noticed 66. It never got to 68 either, but the 66 on the fermometer started to turn blue, so it was heading that way. It may have been a 3 degree swing, but I am trying to keep it as steady as possible. The blow off tube is going pretty crazy right now.

I used 1.5 eleven gram packets of Danstar Nottingham Ale yeast which recommends 57-70 degrees. I will be bottle conditioning in a cabinet over my refrigerator (probably 70-75 degrees.)

 

[steakandale]

How long should you be careful about maintaining temps? You should be careful with it throughout primary. The most active phase of fermentation, around 3-4 days is mainly when you might see the biggest jumps.

You are within ideal range though for the remainder. This is a good thing to know so early on - and you measured it yourself to see that both ambient and internal temp can be as much as 10 degree swing.

After those 3-4 days, it passes a hump in activity and the temps will also calm a little. Also, not every time will be like that. some are more steady.

Those "fermometer" stickers can span a couple numbers. Some here say they are off by a bit. I haven't measured it myself. I like them and use them though. I just dont realy on it exclusively.

 

[MrStrangeBrew]

the more control over the temp the better the fermentation will be.

 

[McDingleberry]

the more control over the temp the better the fermentation will be.

Yeah, that's what I've read. I actually started building a fermentation chamber yesterday out of some lumber that was left in my shed by the previous homeowner. It probably won't be done for a month or two though, so I am a bit worried about this batch.

 

[McDingleberry]

How long should you be careful about maintaining temps? You should be careful with it throughout primary. The most active phase of fermentation, around 3-4 days is mainly when you might see the biggest jumps.

You are within ideal range though for the remainder. This is a good thing to know so early on - and you measured it yourself to see that both ambient and internal temp can be as much as 10 degree swing.

After those 3-4 days, it passes a hump in activity and the temps will also calm a little. Also, not every time will be like that. some are more steady.

Those "fermometer" stickers can span a couple numbers. Some here say they are off by a bit. I haven't measured it myself. I like them and use them though. I just dont realy on it exclusively.

So, if it gets up to say 75 degrees in 3 weeks, it could cause some off flavors even though the fermentation is 99% done? I'm doing OK keeping it down right now, but if we get temperatures over 70, I might not be able to.

 

[Homercidal]

I think you are doing fine. A couple of degrees is no big deal. You really want to avoid chilling to much too fast, as the yeast can go into a mode where they store food and begin to shut down. Feel free to raise the temp to upper 60's after the initial fermentation is complete. Since the yeast is making heat right now, it might be too cold after it start to slow down. Once you get the majority of the food gone, the chance of getting esters from high temps is close to nil.

 

[FensterBos]

Just to clarify, the bucket temp was never at 62, I pitched at 64 and it stayed 64 until yesterday afternoon when I noticed 66. It never got to 68 either, but the 66 on the fermometer started to turn blue, so it was heading that way. It may have been a 3 degree swing, but I am trying to keep it as steady as possible. The blow off tube is going pretty crazy right now.

I used 1.5 eleven gram packets of Danstar Nottingham Ale yeast which recommends 57-70 degrees. I will be bottle conditioning in a cabinet over my refrigerator (probably 70-75 degrees.)

Sorry, I used the 62 to 68 to 64 has just an example; wasn't saying that it was your situation.
I think everything looks pretty good. As long as you don't have any huge temperature swings during your primary fermentation you'll have a nice beer. I use Nottingham all the time and have had no problems with it.

 

[McDingleberry]

I think you are doing fine. A couple of degrees is no big deal. You really want to avoid chilling to much too fast, as the yeast can go into a mode where they store food and begin to shut down. Feel free to raise the temp to upper 60's after the initial fermentation is complete. Since the yeast is making heat right now, it might be too cold after it start to slow down. Once you get the majority of the food gone, the chance of getting esters from high temps is close to nil.

Awesome, this is what I like to hear. Ideally, I'd like to let is sit for month, but I was afraid that temps over 70 degrees towards the end might ruin it.

 

[OldManHouston]

Once the yeast starts slowing down and it cools back down a few degress (maybe after 4 days or so) I like to slowly raise the temperature up to 70-72 do give the yeast a chance to finish up and dry out the beer more before the yeast flocculate out. At this point you should be past the point where any fusels and undesirable esters will be produced so it's not a problem. You don't want to condition the beer in a hot environment, but in my experience high 60's, low 70's is usually fine after primary fermentation has completed.

The key is to experiment with that type of temperature control over a few batches and see what works for you.

 

[McDingleberry]

Once the yeast starts slowing down and it cools back down a few degress (maybe after 4 days or so) I like to slowly raise the temperature up to 70-72 do give the yeast a chance to finish up and dry out the beer more before the yeast flocculate out. At this point you should be past the point where any fusels and undesirable esters will be produced so it's not a problem. You don't want to condition the beer in a hot environment, but in my experience high 60's, low 70's is usually fine after primary fermentation has completed.

The key is to experiment with that type of temperature control over a few batches and see what works for you.

That's interesting. I plan to do another batch of this beer, but use all Cascade hops instead of the Kent Goldings so I can compare the hop varieties. By that time I should have my fermentation chamber going, so maybe I will give that a try. I have a felling this batch will be up around 70 near week 3.

 

[MrStrangeBrew]

they sell an electric belt that you cant strap around your fermenter and keeps it at a certain temp. maybe try using one of those and put it in a cooler place

 

[McDingleberry]

they sell an electric belt that you cant strap around your fermenter and keeps it at a certain temp. maybe try using one of those and put it in a cooler place

Yeah, I've seen those. The problem is that in a few weeks, I won't have a cooler place. My whole house will be over 70. By June I plan on having a fermentation chamber setup that can hold 6 carboys though, so hopefully this will be the last time I have this problem.

 

[Homercidal]

That's interesting. I plan to do another batch of this beer, but use all Cascade hops instead of the Kent Goldings so I can compare the hop varieties. By that time I should have my fermentation chamber going, so maybe I will give that a try. I have a felling this batch will be up around 70 near week 3.

The difference between those hops is going to be huge. I like to keep my Nottingham at around 62 ambient. That would allow it to heat up to 65-68 during the ferment, but then you'd want to bump it up as it slows down as mentioned before.

This winter I had no fermentation chamber, but I had a controller. I got a free broken freezer from a guy at work and I installed a very small space heater inside. So I fermented and lagered an Oktoberfest. Strange to think that you'd need a heater to brew beer, but it was too warm in the house and too cold in the garage. It was my only option.

The method worked bery well, but I underpitched the amount of yeast I think. I think I can detect some off flavors.

Now I have a large upright tha tworks, so I'm all set for summer. Hoping to trade another upright for a small chest freezer so I can do Ales AND Lagers this summer. Just need to pick up another controller.

 

[McDingleberry]

The difference between those hops is going to be huge. I like to keep my Nottingham at around 62 ambient. That would allow it to heat up to 65-68 during the ferment, but then you'd want to bump it up as it slows down as mentioned before.

This winter I had no fermentation chamber, but I had a controller. I got a free broken freezer from a guy at work and I installed a very small space heater inside. So I fermented and lagered an Oktoberfest. Strange to think that you'd need a heater to brew beer, but it was too warm in the house and too cold in the garage. It was my only option.

The method worked bery well, but I underpitched the amount of yeast I think. I think I can detect some off flavors.

Now I have a large upright tha tworks, so I'm all set for summer. Hoping to trade another upright for a small chest freezer so I can do Ales AND Lagers this summer. Just need to pick up another controller.

Well, the crazy part of the fermentation is pretty much over, so I moved back to a warmer part of the house. I pretty much kept it at 64-66 degrees since Sunday, so I think it should be good. I actually took a gravity reading just for the heck of it, and it's down to 1.020 from 1.064, and it's still bubbling a bit, so I'm hoping it won't have a problem getting to 1.012 or so. And it tasted GREAT. I can't wait to try it out of a bottle in 5 or six weeks.

Right now I am building a fermentation chamber in front of window in a spare bedroom. I basically built a table that sits just under the window sill that is 56" X 34". It should hold 6 fermentors. I am then going to build a box frame on top of that, and use foam insulation as the walls, and cut a hole for a window AC unit. Here is a picture of the table so far(It still needs plywood). I hope to get the top portion done within a couple of weeks.