Open fermentation temperature control?

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youngson616

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Is this a thing? Seems like most people use a style that likes the tempature of a basement perhaps and ferment openly down there. Just curious what others do for this as far as open ferment temp control.

I open ferment in a bucket in a closed chest freezer with my tempature probe in an open cup half filled with sanitizer solution. The temp swings are moderate, about 3 degrees right now, would like closer to 1 +/- . This time around I rigged up a plastic siphon clamp and shoved it through my carboy probe, and slid the probe in there.

What are yall doing??
 
Here's what the new tryout setup looks like...
 

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Great question. I guess the question is what kind of beer are you brewing, and why use open fermentation?

I did an open fermentation for a weissbier and weizenbock, but ambient basement temperature was fine (65-68F). Eric Toft at Schönram Brewery uses open fermentation and makes some of the best beer in Germany.

I considered open fermentation for some lagers, and I thought I could leave the chilling coil in the fermenter (I use a stainless conical), similar to what you are doing. Another option would be to put the bucket in an ice bath and control the temperature of the bath.

I agree that the chest freezer method will have some temperature swings because of the air gap and lag between cooling and the probe. Maybe a PID controller could drop your swings to 1 degree? Whatever you use, good luck and good beer!
 
Great question. I guess the question is what kind of beer are you brewing, and why use open fermentation?
This beer here is a dunkleweizen, and I am doing open fermentation because I ran my last hefe open fermented and it was the best one I've ever had. Lots of local micro brews around here use this method with weissbiers and swear by it. Im trying to duplicate the result with the dunkle. Im on hour 24 right now smells like toffee clove biscuit banana
 

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I agree with open fermentation on weissbier, dunkelweiss, weizenbock. Mine turned out so well it surprised me. In my ferments, whenever I put the lid on the bucket, I would get a volcano of foam within a few hours. So I definitely concur with your plan.

Out of curiosity, what was your recipe? I may want to brew one myself. I used a recipe modeled off this: Recipe: Kelheim Weizendoppelbock, in the Style of Schneider Aventinus

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Does anyone go right from primary open fermentation to bottling/kegging no secondary?

I would like to try to rack this into a bottling bucket and bottle as soon as its attenuated (probably 4 days total). I been doing secondary after for a few days always and its like it develops an odor when it gets racked and sits there and I don't like that haha
 
Out of curiosity, what was your recipe? I may want to brew one myself. I used a recipe modeled off this: Recipe: Kelheim Weizendoppelbock, in the Style of Schneider Aventinus
This was one of my own thought up recipes. That's pretty much most of what I do now as I have a brew store nearby. I could share it anyhow-

5.5/lbs dark wheat
3/lbs pils
2/lbs dark munich 20L
.25/lb caramunich III
.25/lb chocolate
.5/lb caramel

I used a Hefeweizen yeast, white labs 300 and hallertauer hops. I know it seems heavy on special malts, but my last dunkle I did wasn't toasty enough with a small amount. This one seems to be right on point so far!
 
Im at about 3 days (68 hrs) and this beer is practically done. Krausen went down and 1.012 gravity this morning. Can I bottle this already after racking?
 

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Can I bottle this already after racking?
Depends on the yeast strain. Some top-cropping English strains are so flocculant the wort is almost bright during fermentation and the beer can be packaged soon after fermentation finishes. You can put a small glass of the beer in the fridge for a few hours then see how much sediment drops out. Ideally, very little. Best to package bright beer generally.
 
Ok gotcha. Im asking because I always secondary, then it almost darkens more there, and then developes an undesirable odor as well. Its white labs 300 hefeweizen yeast if that matters. Im wanting it to taste semi yeasty, its a dunkleweizen
 
Hefeweizen is a completely different kettle of fish. One of the few exceptions to bright beer. Not really my thing, tbh. I'd say bottle it when it starts to taste good enough to package?
 
I would recommend not to rush it. Even though the yeast have hit FG, they're not done yet. They have lots of fermentation chemicals and crap to clean up. It's like doing the dishes after you finish cooking -- just let it happen. You won't lose yeasty flavor, but you will lose awkward flavors and suspended protein clumps. Give it a week, then bottle. Or maybe bottle some now and see if you find a difference between 3-day bottled beer and 7-day bottled beer.

For comparison, I brewed a weissbier and weizenbock last year:
Weissbier: 7 days primary, cold crash 3 days, keg. Tasted amazing. Moderate haze, but after a month in the keg it dropped clear and looked spectacular.
Weizenbock: 14 day primary (1.066 OG, it kept fermenting forever!), cold crash 2 days, kegged. Moderate haze, but harder to see due to the darker color. Tasted just incredible.

Good luck!
 
If you think it's done fermenting, and it is at terminal gravity (FG) you should probably bottle it or close off your fermenter. If it is done and you leave it open, then it may take on oxygen, which you don't want. Open fermentation is a balancing act, like most brewing processes. If it is done, then package it for consumption. Dunkleweizen is meant to be consumed fresh and aging won't make it better, but could make it worse.
 
Yes, temperature control is just as important with open fermentations. I use a thermowell to monitor temperature.

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I was thinking - open fermentation may benefit from some motion as well. Looks like you are continuously pumping?

I also notice the lid on... and the interesting stacked arrangement. Mind explaining your setup? I'm definitely curious.
 
I was thinking - open fermentation may benefit from some motion as well. Looks like you are continuously pumping?

I also notice the lid on... and the interesting stacked arrangement. Mind explaining your setup? I'm definitely curious.
Not continuously, every 4 hours for 1 minute, after active fermentation starts and air has been purged from the yeast trough on top. Kind of a Yorkshire square, the traditional way to rouse highly flocculant top-cropping English yeast strains. Yeast foam through the yeast hole and get trapped in the trough then get washed back in (every 4 hours) by recirculating wort, which helps rouse yeast floccs off the bottom too. It improves the rate of fermentation, yeast profile/beer and harvests healthy yeast for the next batch. The loosely fitting lid just goes on until fermentation kicks off, usually. Doesn't seem to make much difference either way. I don't use silicone tubing anymore, because, if left for a day or two, I noticed beer samples from the tubing were badly oxidised. Using stainless pipes now.
 
Eric Toft at Schönram Brewery uses open fermentation and makes some of the best beer in Germany.
This was the main reasoning I did an open ferment on a recent pils targeting something similar to Schonramer. Also just did one with a czech pils.

I left the fermenter in my chest freezer and removed the lid once fermentation started in earnest (krausen formed). I cracked the freezer about 4 inches and pulled the drain plug in the bottom to facilitate evacuation of CO2. It seemed to work, as the temp held tight around 50°F (BrewBucket thermowell) and everytime I walked by I did a breathe-test near the fermenter opening and didn't get any CO2 lung burn. I would usually button the lid back up once the krausen started to fall, but I didn't get a chance since I transferred to a keg for d-rest and spunding initiation before the krausen actually started to recede.
 
Ok guys honesty time.....I Made a mistake and read my hydrometer wrong initially. So it read 1.020 at 3 days, not 1.012. I decided that was not the number I wanted to bottle at and racked it to a secondary. I hope it drops a few points in there, the airlock is bubbling away pretty good right now and it had already been a few hours since transfer. Will check gravity after 24 hours
 
Others have said it - don't rush it. You need at least 2 consecutive identical gravity readings across multiple days to know it's done, otherwise you risk over carbing or bottle bombs. Don't bother with another reading in 24 hours if it just came in at 1.020, give it another day with the hopes of your next reading is after it's hit a true FG, then your reading after that is the same. The more you monkey with it the more you run the risk of contamination and oxidizing it.
 
I hear you all on not rushing it trust me I won't. But the idea here originally was to bottle after primary and not do secondary. Unfortunately after the point of 3 days the krausen starts to fall and Leaving the beer susceptible. The result I was hoping for was reaching my target FG in primary. Im not worried about it anymore, I think I figured it out and can accept a minor secondary phase after an open fermentation
 
Can you save some work and basically put a lid on the beer?

Generally secondary is not recommended due to the extra work, the chance of contamination, and certainly to prevent O2 exposure. But... after an open fermentation you've about had as much O2 exposure, and maybe contamination exposure, as one would ever think to see. Secondary for you may not have the "normal" drawbacks.
 
Can you save some work and basically put a lid on the beer?
Yes I could but I don't like that idea and here's why - Any contaminants or bacteria that were exposed to the krausen are now gonna be pressurized and push back into my beer if I put a lid on. That's why I ferment in the bottle bucket, to transfer the beer from under the fallen krausen and leave all of that behind, along with any contaminent sitting on it.
 
Well its still bubbling along in secondary lol. Smells good and looks like it's still making a good amount of co2. Im gonna wait maybe another day to check it , dont wanna dink with it. Can't believe its been so active fermenting at 63*
 

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It didnt even drop a point in the secondary. Left it there for five days. Taste good just didnt attenuate fully. Its bottled, I will be popping a top soon in a few days here.

Seems like most open ferments I see are averaging 1.018 - 1.020 after the 3 days so I suppose I was right there.
 
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