Fermenting in Corny Keg - A Few Questions Here

[geoffm33]

I am fermenting an IPA in a corny keg, first time doing this. Has worked well so far. I have a slightly bent dip tube and a blow off on the gas post.

1) Should I cold crash to compact the trub before I transfer to the serving keg? If so, how would I do that? Should I just remove the blowoff and reinsert the gas tube and post? If I do that and fill the headspace with CO2 will the slightly carbonated beer that results pose an issue when I transfer?

2) To transfer I plan to hook a jumper from liquid out on the fermenting keg to liquid in on the serving keg. I have a swivel flare nut on one of the liquid disconnects and will dump whatever trub comes out first, then connect to serving keg. I'll leave the pressure relief valve open on the serving keg and apply CO2 to the fermenter. Should I purge the serving keg with CO2 first? Chill it?

Any other advise or suggestions?

Thanks!

 

[Braufessor]

* Definitely purge that serving keg. I fill mine all the way with star san and push it out with CO2.

*I would unhook that blow off and put the post on so oxygen does not get sucked in when you cold crash. Hitting it with some CO2 first will help keep pressure on the lid when it cools down. That CO2 won't carbonate the beer significantly and won't cause a problem.

*Cold crashing may or may not be needed. One of those things you need to kind of get a feel for over several batches and decide if your beers and your set up needs it. Generally, I do not cold crash ales before moving to a serving keg.

 

[c673986]

My suggestions:
-Always cold crash. You'll get more and cleaner beer. Doesn't matter if you replace the blow off at this point. It's already done fermenting and you're going to chill it down. Any carbonation in there will be minimal.

-Remove the poppet valve from you dip tube side of both kegs on the liquid side. Remove the valve from you ball lock connector. Any trub you get in the transfer will quickly clog those up.

-don't worry about purging with co2, there's some carbonation in there usually and it's not going to be exposed too long.

The trub is going to be you're biggest problem since you're really not going to know where it's at in relation to the dip tube. I'd have a siphon as a backup plan in case everything get clogged up. you may want to leave some headspace in your serving keg for adding gelatin in case you get a bunch of trub in there.

 

[geoffm33]

Thanks for the input, dry hopping on Saturday then kegging in the middle of next week. Fingers crossed.

 

[popsicleian]

Thanks for the input, dry hopping on Saturday then kegging in the middle of next week. Fingers crossed.

I don't know exactly what your dry hop plans are, but you should definitely avoid loose hop material in the keg fermenter--I made the mistake of doing that once, and my poppet got hopelessly clogged when I tried to transfer to a serving keg.

 

[geoffm33]

I don't know exactly what your dry hop plans are, but you should definitely avoid loose hop material in the keg fermenter--I made the mistake of doing that once, and my poppet got hopelessly clogged when I tried to transfer to a serving keg.

I have a @wilserbrewer hop bag that I plan to use.

 

[CudaJoe]

I am going to start an Oktoberfest style beer in August with a lager yeast. I want to ferment in my kegerator using my kegs as well. I am going to do a 9 gallon batch and split between two corny kegs (4.5 gal) each. With it being a lager, and using some Fermcap S, I am hoping the krausen is low and doesnt clog the gas disconnect.

I just dont know if its better to take off the gas post and connect a tube or use the gas disconnect. I feel there are benefits for each. Less likely to clog with the no post at all but no oxygen contamination when there is a gas disconnect should it clog and I need to remove it to clean it.

The other thing I am uncertain of is trub. Wouldnt trub transfer from the fermenting keg to the serving keg? I dont want to damage the draw tube like some suggest. Id like the keg to still function as a keg in the future.

 

[popsicleian]

I am going to start an Oktoberfest style beer in August with a lager yeast. I want to ferment in my kegerator using my kegs as well. I am going to do a 9 gallon batch and split between two corny kegs (4.5 gal) each. With it being a lager, and using some Fermcap S, I am hoping the krausen is low and doesnt clog the gas disconnect.

I just dont know if its better to take off the gas post and connect a tube or use the gas disconnect. I feel there are benefits for each. Less likely to clog with the no post at all but no oxygen contamination when there is a gas disconnect should it clog and I need to remove it to clean it.

The other thing I am uncertain of is trub. Wouldnt trub transfer from the fermenting keg to the serving keg? I dont want to damage the draw tube like some suggest. Id like the keg to still function as a keg in the future.

I've always just used the disconnects with some tubing into a glass of Starsan. I've had some blowoffs, but never any clogs.

I have some fermenting/serving kegs that have cut diptubes and some that don't. It significantly decreases, but does not completely eliminate the amount of trub I get during transfer (I still have to run off some of the gunk first--once it starts running clear I clamp the tubing and attach to the disconnect on the serving keg). I can still use those kegs as serving kegs, though--I just put a piece of silicone tubing (1/4" works well) on the end of the diptube to replace the length that was cut off.

When I ferment in kegs with uncut diptubes, I find that I get much cleaner transfers when I cold crash for at least a couple of days first--that usually compacts the trub enough that it stays put after I run a pint or two off initially.

 

[geoffm33]

Transferred from the Corny fermenter to my serving keg last night. Worked perfectly.

* Filled serving keg with starsan
* Jumped beer out to beer out
* Applied ~5 PSI to fermenter
* Opened PRV on the serving keg

I saw a video today of this process but with a gas out on the serving keg to a jar of starsan instead of opening the PRV. May try that next time.

 

[acidrain]

I use a a Sanke for fermenting, but If I was using a Corny, I would buy an extra lid, and add one of Bobby's bulkhead dip tube fittings and transfer from that.
Racking cane: https://www.brewhardware.com/product_p/sscane38x29.htm
Weldless bulkhead: https://www.brewhardware.com/product_p/truebulkhead38comp.htm
Silicone o-ring: Doesn't carry it? I bet he does... ask him.
This way you can slide the cane up and down under pressure to pull off just the beer and leave the trub and hops behind.

 

[schematix]

Guess it's a little late now but I wrote a thread on corny keg fermenting with an emphasis on reducing oxygen. See link in sig.

Nothing will be more kind to your IPA then reducing oxygen exposure to insanely low levels.

 

[Braufessor]

Guess it's a little late now but I wrote a thread on corny keg fermenting with an emphasis on reducing oxygen. See link in sig.

Nothing will be more kind to your IPA then reducing oxygen exposure to insanely low levels.

That is a great write up and strategy.... it is on my "to do" list for my next set of lagers. Thanks for taking the time to do that.

 

[schematix]

That is a great write up and strategy.... it is on my "to do" list for my next set of lagers. Thanks for taking the time to do that.

FYI there are a few minor revisions to the process that were noted in subsequent replies ... some of them made it back into post #1, but others were discussed after HBT locked editing of the original post.

There are a lot of variations on this process.

The trick with racking with both gas and liquid lines attached works just as well with a conical (seen it with SS Brew Buckets too), or even a plastic bucket ferm with a spigot. In that way you're never introducing atmospheric air to anywhere in the system. You need a tiny bit of pressure to start the flow but once its going its self sustaining.

There are also some ways to water purge without having to cut your dip tubes - which is not easy without the right tools!

 

[FunkedOut]

Got a plan for dry hopping in the fermentation keg. Put it into play yesterday.

Sanitized a hop sock and some thin nylon thread in a jar of starsan.
Filled sock with dry hop charge (and a stainless bar for weight) and tied it off with the thread.

After pitching yeast into keg, I seal it up and pressurize with pure O2, shake it up for a while then vent.

Now I removed the safety valve, removed the lid and fed the thread through the safety valve opening, then reinstalled the safety valve.

I only let the bag down far enough to hang in the air above the beer.
Once fermentation is done, I will quickly pull the safety valve ring, allowing the hop sock to fall to the bottom.
It worked perfectly during the dry runs.

The thread is thin enough that the valve still holds pressure just fine.
Just have to remember to sanitize the thread again (or cut it) before pulling the ring.