Question about force carbonation

[chichum]

I've been doing a lot of reading about force carbonation and I'm a bit confused about one thing. I am going to be kegging and bottling a sparkling wine in the near future. I want to carb it to around 5-6 carb units. From reading, keeping it a 34 degrees and 37# over two weeks is the key. My question is about the shaking/rolling method of carbonating. If I were to put the pressure to 37# and shake the keg until I no longer have CO2 entering the keg, have I reached my desired level? Is that technically the same as if I left it under that pressure for 2 weeks?

Again, say I have a beer I want to carb to 2.5 units - If I am at 34 degrees, can I just put the CO2 level at 9psi and shake the keg until I no longer hear CO2 entering into the keg and then I'm at the right level?

I guess what I don't understand is people say jack the pressure up to 60psi and shake it a few times to do a quick carb of the beer. Doesn't it make more sense to put the pressure at the level you desire and shake it rather than much higher?

 

[hunter_le five]

If you crank up the pressure you will absolutely get carb faster, but will risk over-carbing.

If you set the pressure to you equilibrium pressure and shake, it will carb faster than the traditional set-and-forget method, but slower than crank-and-shake. The upside is you will not over-carb the beer. The downside is you are going to have to do a lot more shaking. However the only real way to determine that you've reached your carb level is by drawing off a sample and taste-testing it.

Personally I prefer the set-and-forget method myself, as it makes consistent predictable results.

However, if you are in a hurry, I would suggest you set to your desired serving/equilibrium pressure, shake the hell out of it until you are tired, and then leave it alone on the gas at least overnight. Then draw a sample and see where you are. Repeat if necessary. This will get you there faster than set-and-forget, and you won't risk over-carbing.

Unless your beer/wine is clear going into the keg, though, please be aware shaking will result in a cloudy beverage.

 

[TopherM]

It's not that simple. In your beer example, where you want 2.5 units at 34 degrees and set the pressure to 9psi and start shaking.....it WILL NOT be fully carbed once you no longer hear CO2 entering the keg. It is only going to be partially carbed. You would have to wait for the beer to settle, then repeat, then wait for the beer to settle, then repeat, until the beer can no longer absorb anything at 9psi. It would take several shaking sessions before you could absorb enough to reach that equilibrium. I don't know the exact science, but something about the foam filling the headspace makes it so the beer is no longer absorbing CO2. You have to wait for it to settle and for the CO2 to refill the headspace, then do it again and again.

In the end, if you have the time, the "set it and forget it" method is much less of a hassle.

 

[SC_Ryan]

On a related side note. I carbed an pink lemonade vodka drink in a corny. We wanted to get it to near champagne levels of carbonation so we shook it up really well at 35ish degrees at around 45psi. It carbed up nicely but it seemed to crush the carbonation during dispensing. Even dispensing around 2psi it was creating a lot of foam and flattening the cocktail a fair amount. You might want to rig up an extra long beverage line for dispensing your sparkling wine. Just a suggestion. Good luck.

 

[DrunkleJon]

For higher carbonation levels you need longer beer lines to slow the dispensing of the beer/what have you. Otherwise the speed of dispensing will knock the CO2 out of solution and you will get foamy/flat pours.

 

[tootal]

It's not that simple. In your beer example, where you want 2.5 units at 34 degrees and set the pressure to 9psi and start shaking.....it WILL NOT be fully carbed once you no longer hear CO2 entering the keg. It is only going to be partially carbed. You would have to wait for the beer to settle, then repeat, then wait for the beer to settle, then repeat, until the beer can no longer absorb anything at 9psi. It would take several shaking sessions before you could absorb enough to reach that equilibrium. I don't know the exact science, but something about the foam filling the headspace makes it so the beer is no longer absorbing CO2. You have to wait for it to settle and for the CO2 to refill the headspace, then do it again and again.

In the end, if you have the time, the "set it and forget it" method is much less of a hassle.

It has been my experience that if you do the shake method you will get pourable beer within the hour. You can shake it at the right pressure and temp until you don't hear anymore CO2 entering the keg but it takes a lot of shaking so here's my method and it seems to work fine and not take so long:

Get your beer as cold as you can. I usually get it between 30-35 degrees. Hook the CO2 up to the OUT side of the keg. This allows the CO2 to bubble up from the bottom which is easy to hear. I set the pressure gauge at 30 psi. I shake for one minute. Then lower the pressure to 10-12 depending on the beer temp and Volumes of CO2 desired. Check your chart. Now continue to shake until you don't hear anymore bubbling. Put the keg back in the fridge and let it set for an hour. I have poured a beer right after shaking and get about half foam but an hour later it pours great. I never keep my kegs connected to the CO2, unless I'm having a party, since it seems to slowly bleed off. I just hit all the kegs once a week just to replace what I've poured off. I get a nice head and great lacing on the glass.