So my question is in regards to temperature and carbonation and their role on bottled beer from a keg. So say if you bottle your beer from your keg at 45’F as an example. You you have purged the bottle of oxygen as well as the head space once the bottle is filled. Assuming that your beer is done fermenting, fully carbonated and had reached equilibrium in the keg, will your carbonation change as the temp of the beer in the bottle changes? What i am getting at is would the beer foam over if you opened say at 70’F leaving your beer slightly flat since i would think the beer could hold less co2. Maybe i am over thinking it but since i cannot control the temp in which people drink my beer at, the last thing i want is a foamy bottle of beer. If i open commercial beer warm, it doesn’t foam over and is still carbonated. How does this work, someone please enlighten me. Thanks
The level of carbonation won’t change in the bottle once it’s bottled and capped, presuming it’s fully finished fermenting.
However, you probably will lose some amount of carbonation going from the keg to the bottles, so having the beer carbed slightly higher than your desired serving volume in the keg, before transferring, is probably a good idea.
With no real way of measuring other than my own taste buds, when bottling from a BeerGun, that I lose approximately .2 volumes of CO2 on the transfer. So if I want 2.5 volumes in a bottle I carbonate to 2.7 volumes in the keg. This is of course trivial and probably not “true” but it seems to be a good working rule of thumb for me.
Chill that beer down to near freezing. This will save you some carbonation loss. Are you using a counter-pressure filler? You shouldn’t lose much if at all.
The Blichmann Beer Gun is the best bottle filler I’ve ever used. I’ve got about 6 different counter-pressure ones, but they all have issues. I don’t use it often, but every time I pull it out, I’m amazed at how well it works.
I’ll offer more praise for the Beer Gun. One-handed operation, the ability to purge the bottle and headspace with CO2, easy to clean. My only complaint is the tiny rubber stopper, which tends to fall off and get lost, sometimes in a bottle of beer! (Thankfully, it was in the first bottle I checked.). John is a really approachable guy, supportive of local clubs and competitions (the winner of the Indiana State Fair competition wins a Boilermaker brew pot), and he attends NHC every year.
+1 to the Beer Gun. It’s so easy to use and maintain plus it yields great results. I chill my beer down to at least 40F but colder is even better. The bottle temp is not a significant factor in my experience.
I typically carbonate the beer in the keg a slight bit more than ideal to allow for some loss in the transfer process.
Gordon, when use the beer gun do you find yourself carbing your beer a little higher to make up for any loss in carbonation when bottling? Or do find the beer gun to deliver relatively the same carbonation to the bottle?
Yes, but that’s what I’d do with any system. It’s the nature of putting a carbonated liquid into an open container. As well as venting the keg before filling. Chilling the beer and bottles before bottling time minimizes those losses, though.
Normally, I have the beer at a good carb level at serving temp. Then I chill it down to near freezing and hit it some more with gas. Let it sit a day or two, then fill.