• Welcome to the new forum! We upgraded our forum software with a host of new boards, capabilities and features. It is also more secure.
    Jump in and join the conversation! You can learn more about the upgrade and new features here.

New to Kegging - Carbonating vs. Serving/Storing Temperatures

philm63

Grandmaster Brewer
Joined
Jul 6, 2012
Messages
372
Reaction score
0
Location
Plain City, OH
Just kegged my first brew yesterday and it is sitting in my fridge at 39F with the CO2 set at 12 psi - this is where it will sit for about a week to carbonate (if I exercise restraint).

Question is; when do I raise it from carbonating to serving temperature? Should I wait for the full week then raise it up to serving temperature, or can I let it carbonate for, say, 48 hours at 39F (as I've seen suggested on a few sites) and then raise it to 50-ish for the remainder of the week, or...?

Also, should I store excess full kegs at 39-40F or closer to serving temps?
 
I chill mine at about 40-45 degrees for 24 hours after kegging.  Then, carbonate at 30 psi by rolling keg like a baby for a minute.  If it's under carbed then leave it at 30 psi for additional 12 hours and re-test.  If overcarbed, de-carb it and try again.  Do that and just raise to whatever serving temperature you want. 
 
There's a lot of latitude in the PSI vs. Temperature curve.  I don't know a reason to carbonate at a different temperature than you plan to serve at.  I carb at the same temperature I serve at. 
 
Is there anything to the notion that colder liquid is easier to carbonate?  Maybe I saw it in an article on cold-crashing and carbonating simultaneously, not sure. Seems to me in most cases, cold-crashing to drop "stuff" out of suspension is done at pretty low temperatures (30-ish to 40-ish) primarily in the interest of time.

CO2, as you've noted, has a wide range of temperatures and pressures with which one can successfully carbonate their beer. But curiosity has me by the tail - I'd like to know if there are any advantages to carbonating at lower temperatures, or are the returns minimal such that it would be just as well carbonating at serving temps to save steps.

Do temperatures have an effect on the quality of the carbonation sufficiently to warrant further investigation?
 
This chart suggest you get more volumes at lower psi at lower temps. If time were not a factor it would be easiest to just to carb at serving temp. Assuming there isn't more co2 lost from leaks due to higher pressure.

http://www.kegerators.com/carbonation-table.php

 
There really isn't much sense in fiddling with carbing temps/serving temps.  Just carb at serving temp.  If you insist on drinking at app. 50 degrees, it may take an extra day to carb, but not likely.
 
I just set it at the carbing pressure (usually 10 -14 psi) and let it set for a couple weeks. I've found it tastes better given some time to age so be patient. Every time I've tried the 30psi, rocking it and then lowering ...etc, I've over carbed.

BTW, isn't the carbing temperature/pressure issue really just a thermodynamic equation? I mean higher beer temp requires higher pressures but if you are chilling one side of the equation (beer) thereby requiring lower CO2 pressure (outside the kegerator) it would be the same as carbing the beer inside the kegerator with CO2 at a lower pressure because the ambient temperature would increase the density of the CO2. Hope that made sense.
 
Here's what I do, if it helps:

I have a beer "chest freezer" with a temp controller and 4 taps.  1 CO2 tank & regulator and a 4 port manifold to go to the 4 kegs.  Since I'm not interested in opening it up and turning on / off various CO2 runs everytime I want a beer, I just leave them all hooked up and open at serving pressure (9PSI).  Therefore, all my beer is at the same temp (I can let the ales warm after pouring).  All my beers are at the same carbonation level, 9PSI, my chosen serving pressure.

When I fill a keg, I let it cool in the kegerator overnight.  Then I shutdown all the CO2 lines except the new one.  I force carbonate it at say 20PSI.  I then return the CO2 tank to serving pressure, close the line to the new (higher pressure) keg, open the others.  I let the new one sit overnight and start testing it the next day.  Draw off a beer.  Drink it.  Later or tomorrow, again.  My goal is to bring the new one down to serving pressure.  When I think it's close, I open it to the rest.  This may overpressure the others a little so I drink a couple to bring down the pressure.

Over time, with all lines open, all kegs with have the same CO2 pressure and carbonation level.  For a kegerator with multiple kegs, this is the most straightforward way I came up with.
 
At colder temperatures more volumes of CO2 can be dissolved into the liquid, but I don't know about it happening any faster. Seems to me like an unnecessary step.
 
Since it is your first time with a keg, I would suggest setting you fridge to your serving temp and then let it carbonate.  Skip the 30 psi rolling and shaking.  I would attach your tap and drink a small glass everyday.  It will give you a good feel as to how the beer changes as it carbonates.  You will be able to tell when it is ready.  After it is where you are happy, drop it to 2 to 5 psi for serving.  I personally turn off the gas when I am not serving.  I had a leak my first time kegging and losing a whole tank was enough to persuade me to turn it off when not in use. 
 
Better yet... After you get everything put together hook it up to co2 and Presurize to 30psi. The get a spray bottle with soapy water. Go over every joint connection and lid. If you see any bubble that's a leak. Fix it. After you get no bubbles, close the regulator and leave everything hooked up. Let it sit for several days. After several days it should still be at 30psi.
 
In regards to temperature, dry hopping was not mentioned. Some of the great hop aromas need conditions a little warmer to come out. Room temp for a week will help before going to serving temps. During this time, I give the kegs a short shot of CO2 at 30PSI a couple of times a day before going to dispensing pressure and serving temperature. Helps identify any leakers with minimum CO2 waste.

StarSan mix in a spray bottle is a great way to do a bubble leak check.
 
Back
Top