Fermentation and Temperature Control

I've been reading through the forum for a few weeks now to try to find answers to my questions. I'm about to start on batch #2 and I know that I fermented a little bit on the hot side for the first batch.

I see that there are a lot of threads on the subject of fermentation and temperature, but I was wondering about how critical it was to keep the temp in the required range for the yeast during the different stages of fermentation.

I'm guessing that it's more critical in the primary stages and less in the later stages. Am I thinking correctly, or are all stages equally critical?

If there were a consensus, it would likely be that the first few days are most important to keep in the yeast's preferred temp range.

I would definatly agree with that statement. I dont know how much of a drop you are looking for, but if it is just a couple degrees, then I would take a rubbermaid tub and put your carboy in it, fill the tub with some water, and throw a t-shirt on top of it. If you need a bigger drop in temp and have ac, you can move your carboy closer to the ac vent or even over the vent in a box made from rigid insulation. The temp can then be controlled but adjusting how much of the box is over the vent. These are the 2 methods which I use before I can afford to build my fermentation chamber.

Some great brews have been made with no temp control. On the other hand if you are really worried go to craigs list and buy a 50 dollar fridge of freezer and get a temp control.

For ales I try to start cool in the swamp cooler (65) and then as fermentation ends I'll let it ramp up to room temperature (68 - 70). As fermentation ends the yeast start to get lazy on the harder to process compounds in the beer and the boost in temperature helps keep them active. At the beginning of fermentation is when you want to keep your temperatures cool because during the reproduction stages the yeast through off a bunch of different compounds that you want them to clean up during the end of fermentation. Keeping temps down can help to limit the amount of undesirable compounds and byproducts of fermentation.

... if you don't have the ability to use a fridge. I found this when I started brewing 7 years ago. I fell out of the hobby and restarted recently. I now live in the south and this thing is a must. It's not too expensive to make either. All the supplies can be found at Home Depot or Lowes.

http://home.elp.rr.com/brewbeer/chiller/chiller.PDF

I built one of the things in the above poster's response. Works like a charm. I can get the thing into the 50's...no small thing here in sweltering KY!

I use a rubbermaid tub with ice bottles rotated as needed. I've brewed at temps from 62 all the way to 72 in my 75 degree house this summer. I can keep temps +/- 1 degree of any temp. I want switching out bottles two times a day with this method, even at high krausen. This is the single most important thing I've done to produce better beer.

Throckmorton said:

... if you don't have the ability to use a fridge. I found this when I started brewing 7 years ago. I fell out of the hobby and restarted recently. I now live in the south and this thing is a must. It's not too expensive to make either. All the supplies can be found at Home Depot or Lowes.

http://home.elp.rr.com/brewbeer/chiller/chiller.PDF

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Hey thanks. I was thinking about buying another fridge but this looks like it'll be fine for ale fermentations. If I can find the "2-inch thick extruded polystyrene" , I may have a weekend project.

Ah, available at Lowe's $22.

I can't find 2" thick in my area. I'm thinking of gluing two 1" thick slabs together.

The only thing that I would suggest is to use wooden skewers as dowels when putting the thing together. The instructions talk about just using liquid nails, however that stuff allows a lot of "play" between the pieces. I got pretty frustrated with it slipping and sliding all over the place. I looked in my cubbard and found the wooden skewers (things you use for shish-ka-bob), but them in smaller pieces, and used it to "nail" the boards together on top of using the liquid nails. The skewers hold everything in place while the liquid nails drys. Worked like a charm.

This link is not working, would love to know what your trick is

Necromancer!

A three year old thread brought back to life.

I just recently built a fermentation chiller that holds 4 buckets or carboys. I don't have any build pics, but here are some right after the build. Let me know if u have any questions. I'm no expert, nor do I claim the best build (just works for me).

I built this: Restless Cellars - Photos

It can hold about 20 carboys and is cooled with a 5000BTU window AC unit ($99)

I'd like to see this thing loaded up!!!! Way Kewl

ViolentMinnow said:

I just recently built a fermentation chiller that holds 4 buckets or carboys. I don't have any build pics, but here are some right after the build. Let me know if u have any questions. I'm no expert, nor do I claim the best build (just works for me).

Click to expand...

How do keep the chest cooled? Did you put an a/c unit on it?

I am currently brewing german altbier which is my first batch of beer. I have had the temps around 66-70 degrees, and it says cold fermentation is good for it, but I haven't been able to get it any cooler. It's in a closet with the under house access door cracked opened to allow cool air in. Should I try to do anything to lower it's temperature? It's sitting on top of a skateboard also, not sure if that matters. It is now 84+ hours since I added the yeast.

phillybob said:

How do keep the chest cooled? Did you put an a/c unit on it?

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I bought the thermal controller from Coolerguys.com and 4-60mm high speed fans. I freeze milk jugs of water and change them out once they quit keeping it cool... All depends on how many carboys, what time in ferm, etc.

rideincircles said:

I am currently brewing german altbier which is my first batch of beer. I have had the temps around 66-70 degrees, and it says cold fermentation is good for it, but I haven't been able to get it any cooler. It's in a closet with the under house access door cracked opened to allow cool air in. Should I try to do anything to lower it's temperature? It's sitting on top of a skateboard also, not sure if that matters. It is now 84+ hours since I added the yeast.

Click to expand...

I'd slap on a stick thermometer to check its temp. The ambient temp is going to be lower than ur actual fermentation temp (inside the fermenter)
Without building a cooler, there's not much you can do to keep it consistent. But if ur not too worried about it, u could simply throw some wet towels around it and change them out each day..... When I started brewing it was winter... So my closets were much cooler... As summer came around I got off favors. So I rigged up a small ac unit in my pantry. The problem with this is that my temps were all over the place.. But my new chiller keeps it at a good constant temp...

I'm sure someone more knowledgeable will chime in...I've only been brewing for a few years now.