Seeking some advice for Force Carbing at Room Temp

[Contradiction]

Hi everyone,
I'm going to be borrowing a friend's equipment to force carb a batch of beer I have before I move to a new apt. on Friday.

Unfortunately I don't have a kegerator setup yet, or for that matter a good place to cool the beer before I force carb it.

I'm going to set it to 30 PSI and roll it on the floor for 5 min. to force carb it, but I'm wondering if it's worth doing anything else after that.

I most likely won't have my keezer setup for a month or more at the earliest, so it's not like I'm going to drink it anytime soon. That should give it time for the CO2 to saturate.

I am wondering if there would be any advantage to letting it stay pressurized with the CO2 afterward though?

Most of the directions I have read for force carbing recommend that after you force carb you should reduce pressure to a suitable serving pressure and put the keg in the kegerator afterward. That makes sense if you intend to drink it relatively soon afterward.

I don't have the luxury of doing that but I'm wondering if keeping it pressurized afterward would have any advantage?

In other words, would there be a benefit to leaving it on at 8-10 PSI at room temp for 10-12 hours after I force carb with the roll method?

Or is there no benefit to that?

I could also put the keg in the fridge for the same duration of time, but not with the CO2 hooked up at that point. I'm not going to be able to cool it that way beforehand because I need to do this tonight.

 

[TheHopfather]

30 psi @ 65F should get you 2.58 vol. You should roll the keg until the regulator stops adding CO2 into the keg. When that happens you'll be at ~2.5 vol (depending on what room temp is), don't just stop at 5 min if you can still hear gas going into the keg.

I would leave it pressurized at 30 psi if you are planning on leaving it at room temp. Liquid absorbs more CO2 the cooler the liquid is. So if 30 psi gets you to the vols you are looking for you want to leave it there while its in storage. If you release the pressure and set at say 10 psi the CO2 you've just shaken into the beer will equalize with the pressure in the keg and you'll end up with less carbonation.

If you've got a month before you'll be drinking it why don't you just prime the keg with sugar and let it carbonate that way?

 

[doug293cz]

30 psi @ 65F should get you 2.58 vol. You should roll the keg until the regulator stops adding CO2 into the keg. When that happens you'll be at ~2.5 vol (depending on what room temp is), don't just stop at 5 min if you can still hear gas going into the keg.

I would leave it pressurized at 30 psi if you are planning on leaving it at room temp. Liquid absorbs more CO2 the cooler the liquid is. So if 30 psi gets you to the vols you are looking for you want to leave it there while its in storage. If you release the pressure and set at say 10 psi the CO2 you've just shaken into the beer will equalize with the pressure in the keg and you'll end up with less carbonation.

If you've got a month before you'll be drinking it why don't you just prime the keg with sugar and let it carbonate that way?

I get 2.77 volumes for 30 psi @ 65˚F using: http://www.brewersfriend.com/keg-carbonation-calculator/, but the equations used in that calculator may not be valid at room temp. What is the source of your numbers?

In any case, @TheHopfather 's advice is sound. Just make sure you do about 12 purge cycles at 30 psi to get the O2 level down before you start rolling, otherwise you will be dissolving O2 into the beer. Warm storage and residual O2 are a recipe for oxidation of the beer in a hurry. I can provide references if you wish.

Brew on

 

[TheHopfather]

I get 2.77 volumes for 30 psi @ 65˚F using: http://www.brewersfriend.com/keg-carbonation-calculator/, but the equations used in that calculator may not be valid at room temp. What is the source of your numbers?

Just some random carbonation chart on the internet, seems to be a pretty common one, no idea on its accuracy.

 

[doug293cz]

Just some random carbonation chart on the internet, seems to be a pretty common one, no idea on its accuracy.

That's the chart pretty much everyone uses. Not sure why the BrewersFriend calc doesn't match up. I thought I had checked them against each other, but maybe not in the high pressure, warm temp range.

Brew on

 

[Contradiction]

So I am actually cooling the beer now. When I stopped into my LHBS for MFL connectors I picked their brain about this and they said I'm better off getting the beer cold before I force carb if I can because it's better for CO2 absorption. So since I have an empty fridge in the place I'm moving out of I pulled all of the shelves out of it and put the keg in.

It's going to be chilled in there for about 18 hrs. by the time I get around to force carbing it tonight. I'm going to take a temp reading before I start.

Should I still hit it with 30 PSI for 4-5 min. if that's the case, or should I go by what PSI I see for the temp range on the charts?

Do the charts refer to a longer duration "set it and forget it" type of scenario?

 

[TheHopfather]

Those charts apply no matter how quickly you are attempting to carb the beer, time is not a factor when shaking the keg. You can set the PSI to whatever you'd like, if you set it over the PSI in the chart for the vols you are going for you run the risk of over carbing the beer.

Disclaimer - I am not a fan of the shake the keg method of carbing, it never seems to end well. That being said if it were me trying to do what you are doing I would know the temp of the beer, figure out what carb level I'm shooting for, set my regulator to the PSI indicated on the chart and shake the keg at that pressure (vent the head space too if you're taking temp readings in the keg). It may take a bit longer before the regulator stops adding gas to the keg but you cannot over carb the beer this way.

At home I'll set my fresh keg to 30 PSI for 24 hours, then drop the pressure down to my serving pressure (usually 12 PSI) and leave it for another day or two. The 30 PSI for 24 hours gets me most of the way there and the following couple of days will get me the rest of the way. Good luck with the shaking!

 

[user 204491]

I force carb at room temp (well 63ish F) all my beers, and I use the chart that @TheHopfather linked too.

I wouldn't bother with all that shaking nonsense really, especially if you don't want to drink the beer for a month.

Fill and purge the keg like @doug293cz mentioned, although I do 15 purge cycles @ 30PSI, following his previously linked charts to get the TPO (total packaged oxygen) down to basically 0.

Then I usually leave mine set @25 PSI (again at 63F) for 2 weeks which equates to just about 2.4 volumes of CO2.

When I'm ready to drink, I put it in my keezer, without the gas connected, and then let it cool down for at least 24 hours.

After that I pull the PRV to purge the headspace and connect to my gas lines in the keezer at 12 PSI, which at 40F is also about 2.4 volumes.

This method has worked out tremendously well for me, and I've not had an overcarbed keg since I stopped trying all that "burst carb" business like shaking.