Keg as fermenter

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Chupidacabra

Well-Known Member
Joined
May 20, 2013
Messages
371
Reaction score
26
I've read a few threads in which people talk about using cornys as fermenters.

What are people doing about the co2? Some kind of airlock attachment? Or just letting the keg pressurize?

Any info would be great!
 
Chupidacabra said:
I've read a few threads in which people talk about using cornys as fermenters.

What are people doing about the co2? Some kind of airlock attachment? Or just letting the keg pressurize?

Any info would be great!

I have been told that the co2 is vented through the pressure relief valve at the top of the keg once the co2 has built up enough. I have sugar primed in a corny before and it built up a considerable amount of pressure. When I manually vented it, it shot out of the valve and all over the ceiling. You might be able to get away with using is as a secondary but a catastrophic failure of the valve in the primary could be very dangerous. Just my 2 cents.
 
I use corny kegs as fermentors. Made my own air locks using a standard gas side quick disconnect and basic plumbing parts. I typically set them up like a blow off tube...just run a hose from the gas side to a small container (plastic bottle) containing a water/sanitizer or water/alcohol mix. This way the pressure relief vavle is still in tact...just in case.

Relying on the standard pressure relief valve as the primary means of venting will build up way too much pressure (about 125psi IIRC), unless you manually vent it...which would be very inconvenient during active ferm. I do sometimes leave kegs in secondary w out an air lock, but manually venting them every few days is all thats needed.

Just ordered a "spunding" valve, which is basically an adjustable pressure relief valve, for naturally carbonating in a keg. Traditionally, but with older tech obviously, this technique was used to carbonate lagers over a long period of time. I plan to use it for this purpose during lagering or secondary and continue to use airlock/blow off tube during primary. I dont think a spunding valve would be a good idea for primary because it is more likely to clog (its only designed for venting gas...not trub from really active ferm) and there is no reason to pressurize during primary.
 
Corny kegs are generally rated for 150 psi, and the PRVs are typically set for 85 psi. Either way, that seems pretty high for happy yeast. I prefer fermenting in glass, but if I was going to tie up a keg for fermentation I'd remove the In post poppet and run a blow-off hose...

Cheers!
 
I use corniest as fermenters and I just remove the gas intake post and stick a standard beer line tube to use as a blow off. Works beautifully and requires very little modifications (just unscrewing the post) to the keg. I used to transfer the beer with CO2 as well but it was more hassle then it was worth - I just use a siphon now and I'm pretty happy with the setup.
 
You need to check out the "Closed vessel pressurized fermentation" thread; it has lots of tried and true methods for using a keg as a fermenter. Be careful cause not all regulators have stainless springs eventually rust and stick. Also don't expect to be able to "dial in" a specific pressure, it won't happen with any of the affordable regulators. McMaster Carr sells one that is made of polysulfane (I think) and stainless steel. It works well and is touted in the aforementioned thread.
 
Got some Briess Dark ferm'ng in a 5 gal Corny AWS(as we speak).
Started using keg 'cause had only 1 BB 'boy, and price of those 'boys is ridiculous! Why buy BB when used keg is $40, and is indestructible???
It's my 2nd batch in keg, and no overflow, which was a concern. Kegs are near indestructible, and, if temp is not optimum, they can be cooled or warmed FAST. Batch can be made in portions, with ingredients added stepwise, if necessary. May even be a useful method to cool hot wort?? Rough on the O-rings, so what?
Volume of wort started at 3.75 gal, as I was concerned about overflow, but it was chilly in room last nite, so slowed it down. Plan to add some carapils solution, later, then again, and transfer to 6gal Vintage House 'boy.
Access and exhaust is done like this: I usually san'ze top, and leave it in-place during entire ferm.
Use the standard in and out tubes, not using the poppet posts. Remove the O-rings, stretch a length of gum rubber tubing(lab supply) about 1/2 in down over the flare, put in hole, wrap with plastic wrap, and now you have 2 access ports, one to below and one to above the liquid level. You can gas, take samples, add more stuff, whatever. I have a bubbler stuck in the shorter tube, and the little darling lulls me to sleep.
Yes, yes, the yeast. An occasional swirl, and the yeast settles on the bottom, so, yes, genius, you DO have to be careful where place the out tube.
 
I have not done anything for my brewery yet... I have not even made beer yet but I have made a cook corny keg fermenter lid. I have a thermalwell and blow off port in the lid... Ill post a pic when I can get to it. It actually seems like it should work very good.
 
AlCophile said:
Got some Briess Dark ferm'ng in a 5 gal Corny AWS(as we speak). Started using keg 'cause had only 1 BB 'boy, and price of those 'boys is ridiculous! Why buy BB when used keg is $40, and is indestructible??? It's my 2nd batch in keg, and no overflow, which was a concern. Kegs are near indestructible, and, if temp is not optimum, they can be cooled or warmed FAST. Batch can be made in portions, with ingredients added stepwise, if necessary. May even be a useful method to cool hot wort?? Rough on the O-rings, so what? Volume of wort started at 3.75 gal, as I was concerned about overflow, but it was chilly in room last nite, so slowed it down. Plan to add some carapils solution, later, then again, and transfer to 6gal Vintage House 'boy. Access and exhaust is done like this: I usually san'ze top, and leave it in-place during entire ferm. Use the standard in and out tubes, not using the poppet posts. Remove the O-rings, stretch a length of gum rubber tubing(lab supply) about 1/2 in down over the flare, put in hole, wrap with plastic wrap, and now you have 2 access ports, one to below and one to above the liquid level. You can gas, take samples, add more stuff, whatever. I have a bubbler stuck in the shorter tube, and the little darling lulls me to sleep. Yes, yes, the yeast. An occasional swirl, and the yeast settles on the bottom, so, yes, genius, you DO have to be careful where place the out tube.


This sounds interesting, can you post a picture?

Thanks.
 
Back
Top