Keg conditioning vs force carbonation.

[sawbossFogg]

to answer the original question......

after reading an interesting thread on pressure fermenting....i decided to try my hand at it.

i had experience keg conditioning, which to me is dosing the already fermented beer that's in the keg with corn sugar, beet sugar I.E. whatever a person might use for priming.

force carbonation, shoot the keg with CO2 at specified pressure kept at controlled temp for a period OR roll the keg around let it set and check by tapping.

have done both of these methods but after reading the aforementioned article i decided to ferment till bubbler was showing only one bubble @ minute. then rack over to keg add 1/4 C priming sugar...i use beet sugar.
this kicks the pressures up to just a hair below 40 psig on my spunge valve.
pressures may have gone to 40 psi and activate the preset blow-off but if so i never saw the guage at 40. so far i haven't been around when the blow off has occured, if ever. so i'd say mostly 37-39ish...psig in keg.
i usually leave the beer under pressure for several weeks....then cold crash for a couple days...release the pressure and tap.
i'm VERY happy with this method. the cascading small bubbles and great head to almost the empty class is great. it is especially enjoyable in a dark to medium colored beer. one would swear it was beer gas carbed poured thru a creamer tap.
also this has helped to cut down on gas useage.
since my experience with this method i don't carb anyother way.
yes there is a small amount of trub in the first glass but if i'm careful and not to concerned about every last drop from the carboy the amount will be small and worth the effort and the beer, from then on is Kystral klear. uless a wit or hefe.

GD

This method sounds pretty fun, I've heard a bit about it before. Can you provide any info on the article referenced?

 

[sawbossFogg]

Hey well thanks everyone, I got alot out of this thread and I really appreciate the response, cheers!

 

[JuanMoore]

And if I were to be at a predicted ~2 Volumes CO2 the worksheet you've shared suggests dispensing at 17 PSI.

That doesn't sound right. My guess is that you have the CO2 set at 75% instead of 25%. And once carbed matching the serving pressure to the equilibrium pressure isn't as critical, unlike when using pure CO2. The relatively high pressure of mostly insoluble gas will prevent you from losing much carbonation even if you serve it at a lower pressure. With warmer serving temps like yours, the equilibrium pressure might be so high that it creates issues at the faucet, and you might need to set the serving pressure lower. Based on the info you've given so far, the equilibrium pressure will likely be close to 80psi for 2 vol, which could be problematic. And 2 vol is pretty high for a nitro faucet, especially at warmer temps. If it were me I'd shoot for something lower, like maybe 1.2 vol.

 

[sawbossFogg]

Which part doesn't sound right? When you say set, do you mean the ratio of n2 and co2 in the beergas?
I'm dispensing at 38F. I keep a room at cellar temps, around 45 and that's where I store and force carb. I have been priming my kegs, cause like bottles that's way I've always done it. According to the force carb chart shared and the easy volumes worksheet, I think I should be in pretty good shape w the faucet if I work from the lower end of the spectrum. I do live over 7000 ft which factors into the easy volumes page. Thanks for your assistance. Getting these
priming, force carb, and dispensing issues understood has been a challenge. Lastly, reading other threads sounds like for force carb it gets a bit artsy in terms of applying a given psi at a given pressure for x amount of time in some shaking or lap roll method. The temp and pressure charts are great, but for how long and with what method still seems a matter of debate.

 

[JuanMoore]

Which part doesn't sound right?

The pressure sounds way too low. It sounds about right if you had input 25% N2 and 75% CO2 instead of the other way around. But once you get the correct figures input, it will likely give you a pressure higher than the faucet will be able to pour well anyway.

Lastly, reading other threads sounds like for force carb it gets a bit artsy in terms of applying a given psi at a given pressure for x amount of time in some shaking or lap roll method. The temp and pressure charts are great, but for how long and with what method still seems a matter of debate.

The carbonation charts and calculators tell you the equilibrium pressure. You can simply set it at the equilibrium pressure and wait 10-20 days for perfect carbonation, often referred to as the set and forget method. Or if you're impatient like many brewers you can use any number of "burst carb" methods to speed up the process, primarily cranking the pressure up for a while, shaking/rolling the keg, or both. I suggest avoiding a combination of both, since it's easy to overcarbonate that way, and is a leading cause of the "help, my beer is all foam!" threads.

You can also buy a carbonation stone and quickly carb your beer without any worry of overcarbonation. I have one, but rarely use it since I feel my beers benefit from a couple weeks of cold conditioning while carbonating.

 

[sawbossFogg]

Juan, yeah at 25% CO2, 38F, 2Vols, 7kft, 8%ABV I'm looking at 75 PSI, so yeah thats ridiculous, huh. If I bring it down to 1 Vol that puts it at 30 PSI which acceptable, hmm! To get 1 Vol, I'd be looking at 1PSI at nearly 60F...uhg!

The second part is a pretty good synopsis. Last dumb question; I like to set it at a pressure and wait, question: does it need to stay at that pressure on the regulated tank or like I have my stout now, pressure applied, removed and stowed? Seems like it'd need to be hooked up to work toward equilibrium over time, but I don't have multiple CO2 regulators. Possibly periodic exposure and a little rolling is in order?

 

[JuanMoore]

Juan, yeah at 25% CO2, 38F, 2Vols, 7kft, 8%ABV I'm looking at 75 PSI, so yeah thats ridiculous, huh. If I bring it down to 1 Vol that puts it at 30 PSI which acceptable, hmm!

My suggestion is to carb it between 1.2 and 1.6 vol, and then serve it between 25 and 35 psi, whatever pressure it seems to pour best at within that range. Like I said before, when using beergas to serve, the carbonation isn't going to change much even if the serving pressure is less than the equilibrium pressure. If it does change too much for you, you could try finding a beergas blend with more CO2.

Last dumb question; I like to set it at a pressure and wait, question: does it need to stay at that pressure on the regulated tank or like I have my stout now, pressure applied, removed and stowed? Seems like it'd need to be hooked up to work toward equilibrium over time, but I don't have multiple CO2 regulators. Possibly periodic exposure and a little rolling is in order?

Yes, you need it under constant pressure while it's carbing since it's absorbing CO2 the entire time. Once carbed it no longer matters.

And the 10-20 days I mentioned for the set and forget method is using CO2. Beergas will take much much longer. If you're still intent on carbing with beergas, I'd suggest doing it at low temps so that you're not dealing with dangerous pressures, and buying a carb stone so that it doesn't take forever. You might also inquire about a beergas blend higher in CO2 next time your tank runs empty.

 

[sawbossFogg]

I suppose thats about the nut of it, no I'm not going to try and carb with the beer gas, this thread has thoroughly cleared that up! The stone sounds interesting as the force carb alternatives are that and the shake methods that I'm currently relying on or an additional tank and regulator (it seems).

What a great set of reasons for good old natural priming, wow I feel like I've traveled full circle through a complete logical sequence I'm much more well informed. Thanks for your time.