Corny kegs for fermennting?

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.

AlkiBrewing

Well-Known Member
Joined
Nov 27, 2011
Messages
100
Reaction score
2
I'm just getting getting set up to start kegging and was wondering about using Corny kegs as a fermenter. Would appreciate any input/advise, pros & cons. Thanks!
 
I've done it before, but wouldn't do it again. For one thing, you'll get maybe 4-4.5 gallons out of a corny keg (5 gallon keg). For another, you need to modify the keg in order to ferment in it. At the very least, you pull the gas post, slip a short piece of tubing over the fitting, to secure the airlock to. Or you get one of the fermenting lids, or make one yourself. Personally, more trouble than it's worth.

I DO ferment in adapted sanke kegs though. I use tall 1/4 bbl kegs for my normal size batches (of beer). I have an adapted 50L keg for larger batches too. I also have several 1/6 bbl kegs that I use for mead and such (smaller volumes). I've adapted these to include a gas post on the top of them. I then use one of my sanke fermenter caps (my own design) so that I can ferment in them, have a thermowell in the middle, and then use CO2 to push the finished beer out of the keg. I have dip tubes cut to leave a certain amount behind in the kegs, so transfers are pretty easy.

If you can't score some sanke kegs for fermenting, then I would advise continuing to use what you are now.
 
I do pressurized fermentation in corny kegs without any modifications to the keg.
You must use fermcap to do this or you will loose too much beer for this to be an effective fermentor.
I plug in my "blow off catcher" into the gas in line and install a spunding valve for pressurized fermentation.
Lots of threads on how to do this, I also use the same setup for a traditional fermentation just without the spunding valve and a little sanitized (or pre-boiled water if I want to top crop yeast) water in the "blow off catcher" to create an air lock.

7362-6525.jpg

7364-6527.jpg
 
I've probably done a dozen batches in cornies. Use some fermcap, remove the gas post and slip some tubing over the threaded post and attach an air lock, you'll be fine. Do it once or twice and see how it works for you.

The down side for me was cleaning the keg when done. Getting all that trub out was brutal.

I'm back to better bottles now.
 
Has anyone had any experience carbonating in one of these like a giant bottle conditioning?
 
I've done some 3 and 4 gallon batches in cornys. I'm currently using one for a secondary for a sour beer. It's a very tight fit with five gallons. I have to be careful about opening the lid to avoid getting it in the beer.

With fermcap you should be able to fit a full five gallon batch in it.

Yes, cornys can be naturally carbonated.
 
i'm now a habitual corny fermenter since my temp control system is based around one, and it fits perfectly with my 20L system
https://www.homebrewtalk.com/f51/my-ugly-peltier-temp-control-junk-350722/
the size limitations concerns are valid but indeed you can maximize space with fermcap, that stuff is a dream, and by adding a bit of pressure with a spunding valve. i don't think cleaning is a problem at all; a rinse in hot water (with a hose) and an overnight oxyclean soak, all that gud comes right off
i either ferment with no pressure, with the out dip tube removed (replaced by an in tube) and a blowoff tube on one of the ball locks, or with the out tube in place and crank up the pressure towards the end to carbonate in the keg, then pressurized transfer to a lagering/serving keg.
 
I just did this for the first time 2 weeks ago. Instead of ferm cap (didn't have any) I split my batch into two 5gal cornys. I have slightly under 3gal in each keg. I pulled out the liquid dip tube and post, and just put 1/2'' ID tube over the liquid outlet, and secured it with a hose clamp. With about 2 gallons of head space, I got no blow off out of the keg.. seemed to work great. No permanent modifications were made to the kegs.

My problem now is trying to figure out how to get the beer out, and leave the yeast cake in tact so I can then wash the yeast. Tonight I will attempt to push it with CO2. My plan is to bend a dip tube (this is where I'll be guessing though since I have no idea how thick the cake is) so that I will just collect the beer at first. Then I will take a straight dip tube, insert it, add my sanitized "wash" water to the keg, swirl, and hopefully be able to push the yeast out. I'm not sure if this will work as smoothly as I'm hoping for though.... I'd love to hear some tips from the guys who have done this before.

As of now, I would definitely continue to use kegs. I brew by myself for the most part, and lifting 2.5-3 gal in a keg over the wall of my chest freezer ferm chamber is a lot easier then lifting a full glass carboy.
 
I always ferment in corny kegs. I just clamp a 1/2" vinyl tube over the gas in post. I usually use fermcap - it helps. I typically get between 4.5 and 4.75 gallons out. I just siphon the beer out into a bottling bucket (don't actually keg yet). For washing yeast, I just add boiled (then cooled) water, slosh around to get the cake in suspension and then siphon that out into a sanitized vessel. Cleaning is no problem - PBW overnight (could probably be shorter) then wipe around the top with a rag to get rid of loosened krausen crud.

Best part is storing star-san in the keg. When its brew day, just transfer the keg to a bucket or another keg and your fermenter is ready.
 
mjohnson, can you tell me what you are using that is long enough to siphon out of a keg? I don't think my current racking cane is long enough...
 
Sure. I've been using an auto-siphon. Its not the 1/2" one - its the next size down (I purchased the wrong one). I have to reach in just a tad to get to the very bottom. If I had the 1/2" one, I think it'd be perfect. One other nice this is that the yeast/trub collects nicely in the domed bottom. You can siphon to the edge of the keg and get nearly all the beer and leave most of the cake. Full disclosure, I keep most of the trub out of the fermenter in the first place.

Once I get a C02 tank, I think I'll bend a diptube so its up by the edge of the keg and just push the beer out that way.
 
Back
Top