help with force carbonation

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i don't yet have a a kegerator, just a cylinder and regulator, a few cornies, and everyone's favorite DIY bottle filler. so i'm wondering what happens when i achieve my desired volumes of CO2 in my keg at room temperature, bottle, and then put the bottles in the fridge. do i have to worry about the temperature changes? what if i carbonate a keg at room temperature, and then put it in the fridge. i'm guessing all i have to do to serve it is release the pressure and re-attach the CO2 at serving pressure?

thanks!
 
If you force carbonate at room temperature, bottle & then chill, you'll have flat beer. Regardless of how careful you are, the beer will degas during the fill.

A better idea is to prime, fill bottles and put the rest in the keg.
 
Beer absorbs more CO2 at colder temps, so carbing at room temperature is undesirable.

Either chill the kegs while carbing or prime like David suggested and chill before serving. Just remember to pull off a pint or two of yeast sediment if going that route.

:mug:
 
thanks for the advice. i just racked into a keg and was planning on putting it and the gas into the fridge to carb, but the cylinder won't fit. so what if i carb at room temp (at 31 psi), then purge the pressure, re-pressurize to the pressure i'd need at fridge temp (13 psi) and put the the keg in the fridge. after a day it should be cold AND have the correct volume of CO2, and then i could bottle!? please let me know if this will work!

thanks
 
You wouldn't need to depressurize before you put it in the fridge, it would take care of that for you as it cooled. Otherwise, that sounds like it should work.
 
Try putting the keg in the fridge for a day so that it gets nice and cold, take it out, hook it to your line, set the pressure, shake it every few minutes for about half an hour, and then disconnect the gas and throw the keg back in the fridge. Check it in a couple of days, and it should be about what you are looking for.
 
It also helps to put a liquid fitting on your gas line and attach to the liquid post. That forces the CO2 to bubble up through the beer for more efficient dissolving while you shake. After you are done shaking, replace the gas fitting and leave the gas hooked up to the gas post.


TL
 
You need DAYS of consistent CO2 pressure to force carb.

if you put it on 12psi, remove the gas and chill it, the beer will absorb a little CO2, and will still be flat as piss.

You'd have to re-pressurize the corny 5-6 times a day, for 2 weeks, to get nice even carbonation.
 
david_42 said:
If you force carbonate at room temperature, bottle & then chill, you'll have flat beer. Regardless of how careful you are, the beer will degas during the fill. A better idea is to prime, fill bottles and put the rest in the keg.

So then .... I am confused. Does this mean counter-pressure bottle fillers are bad? The majority of why I am about to switch to kegging is so that I never have to prime and fill with a traditional filler again. I loved the look of BM's homemade filler, and thought it was a great replacement.

Maybe I just misinterpreted what you're saying, can you expand?
 
Aha - Thanks for clarifying that. I was very worried that my plans had been foiled. Anything I'll be bottling using counterpressure will be cold, so I'm in the clear. Yay!
 
Funkenjaeger said:
You wouldn't need to depressurize before you put it in the fridge, it would take care of that for you as it cooled. Otherwise, that sounds like it should work.

so i'm a little confused. i understand the ideal gas law, and so if i carb at room temperature at a relatively high pressure then the beer will have absorbed all the co2 it can and will have attained the proper carb level. if i leave the keg at high pressure and then cool the beer it will be absorb more co2 and carb more, right? so wouldn't it be a good idea to adjust the pressure down to the pressure level needed at the new, cooler temperature so that you don't over carb? am i missing something here?
 
Nope, while the beer would be more "willing" to take gas at that elevated pressure the headspace volume and thus pressure will drop to the exact same equilibrium it will take to hold that level of carbonation as the temperature drops.
 
wow, really!?!?!?!? so let me rephrase this to make sure i understand. the correct pressure for a given volume of co2 will vary based on the temperature, we all understand this. but once this pressure has been achieved and equilibrium has been reached in the keg then heating or cooling the keg will vary the pressure and not add or subtract volumes of co2. that's awfully convenient!!!

thanks guys!
 
I think Bobby's right. The amount of CO2 in solution depends on the partial pressure, which will equal the headspace pressure at equilibrium. Pressure, volume, and temperature are related by the ideal gas law, pV=nRT. Doing a little back-of-the-envelope math out, it looks like the ratio of the volume of CO2 in the headspace and liquid will remain constant regardless of temperature (and thus pressure) - and since there's a fixed amount of CO2 in the sealed keg, that means that the volume of CO2 in the liquid (ie - carbonation level) will remain constant.

If you purge the headspace at room temperature to drop it to 12PSI, the beer is just going to give up CO2 and re-pressurize the headspace at the higher pressure. That will happen in a matter of minutes, well before the beer finishes cooling down in the fridge - therefore you're really just dumping CO2 right out of your beer.
 
Hey i just stumbled upon your posts researching whether to shake or not to shake during forced carbonation.

My normal procedure has been once i move to my keg let it chill for day down to about 39 in my little beer frig. Next day connect CO2 at 30PSI for a couple days, then drop down to 10psi and serve. I have never bleed or shaken during this process and brew turns out pretty good most of the time, brewing about a year now.

My question if you dont mind is on the shaking. Would that help to carbonate my brew better and or faster or should i keep doing the way i have been. Always tastes a little premature on the carb and why i am researching this.

Any info is appreciated thanks.
 
SenorWanderer said:
i don't yet have a a kegerator, just a cylinder and regulator, a few cornies, and everyone's favorite DIY bottle filler. so i'm wondering what happens when i achieve my desired volumes of CO2 in my keg at room temperature, bottle, and then put the bottles in the fridge. do i have to worry about the temperature changes? what if i carbonate a keg at room temperature, and then put it in the fridge. i'm guessing all i have to do to serve it is release the pressure and re-attach the CO2 at serving pressure?

thanks!

I'm sorry, I didn't get that... I think I was too busy staring at your avatar.... Lol
 
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