I bought some corny kegs a while back and have not started using them yet for anything. I just have the kegs and none of the accoutrements for serving from them.
Can I lager in them without adding CO2? I can fit more kegs in my freezer than buckets or carboys and this would be a desirable option for me. Will the minimal CO2 created after racking into the keg provide me the level of protection I need from oxidation during cold storage (lagering at ~ 34F)? I imagine I’ll be able to fill them to brim.
Same as what Denny said, except I purge my kegs with CO2 before filling them in order to avoid oxygen contact while filling. But I still hit them at the end after the lid goes on to make sure all oxygen is out, and that the lid seals well.
All of what has been said, but I also rock and roll a little, so the beer absorbs some of the gas. Headspace alone can turn into a vacuum (or very low pressure) when that little bit of CO2 is absorbed into the beer at low temperature. If this happens you can lose the seal.
I also follow a similiar method as Gordon and Denny.
When I “kick” a keg, I clean and sanitize, then pressurize to 30 psi while simultaneously purging the air from the keg. I store my kegs pressurized with CO2 until the next racking. This does two things, it ensures their ability to hold pressure over time, and it provides a CO2 environment for the beer to be exposed to during filling, which ultimately reduces oxidation. Then I purge any residual O2, if any that happens to sneak into the keg headspace during filling.
Some of us use the 5 gallon cornys for fermentation for the very space reasons you mention.
There are specially modified corny lids available that will accomodate an airlock and stopper.
A racking cane has to be used to transfer the bright, finished beer to another keg or bottling bucket.
Cleaning and sanitizing a corny can be a bit of a pain, too (compared to a plastic bucket).
Still, I find plastic buckets far easier to clean and sanitize as well as to transfer beer (via spigot).
That’s why I have two fermentation fridges–as I do 10 gallon batches and can only get one bucket in a fridge at a time (along with one or two cornys, if necessary). If you got the space and dough, get two fridges and two Ranco controllers and you’re golden.
By “lagering” did you mean just storing the finished beer at cool temperatures (whether ale or lager), or actually conducting a slow fermentation at cool temperatures, i.e., the process by which lagers are made?
I want to “lager” the lager after primary. I usually bottle, wait for carbonation and the lager in the bottle. I want to try “bulk” lagering to see if that makes the lager more lager-y.
The longer it can remain on the primary yeast cake during lagering often gives great results as there’s more yeast to clean things up. Aging for a month or longer on primary shouldn’t cause a problem so long as temps are controlled.