Another Force Carbing Question

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TheJadedDog

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So, it seems like there are 2 methods to force carbing; 1) set regulator to 10-12 psi and wait and 2) the shake method.

Here's my question, what about setting the regulator to 30psi and leaving it for a day or two, then shutting off the gas until another hit is needed for dispensing. This way you can set your regulator and forget about it. (FYI I have a 2 way distributor with shutoff valves rather than just a y splitter).

Any thoughts?
 
You could do that, although that will be less accurate than just setting it to serving pressure and letting it sit. That is real 'set and forget'. Your way you'll end up tinkering with it all the time, whereas I haven't touched my regulator settings in months.
 
kornkob said:
You could do that, although that will be less accurate than just setting it to serving pressure and letting it sit. That is real 'set and forget'. Your way you'll end up tinkering with it all the time, whereas I haven't touched my regulator settings in months.
I'll have to try that.

Though I lack the patience and with only a 2-keg serving capacity, I lack the cold storage.

My Belgain Blonde went into the keg and fridge last night. Wonder what the odds are that I won't give it a shake this weekend...not too good I suspect.
 
If you shake the crap out of it tonight, maybe for 5 to 10 min and do the same in the morning, it should be carbed later that day
 
Shake it Baby! :ban:
the slow method is only for those with lots of previously carbed beer on hand.:rockin:
 
Hey KornKob, I like your "Theory" signature! and I respect your method of carbing.
but in Theory everyone would have lots of beer on hand and stage it properly for a slow carb method. This is Ideal, but in reality we drink too much and don't plan well enough, and are an impatient breed so; in Theory slow carb. In reality Shake the Begeezes out of her!. honestly no offense, I wish I was in the slow carb position for sure. :tank:
Cheers.
 
I hammer it with 30 psi and shake for 4-5 minutes to dissolve CO2 then back it off to 15 psi and let it sit for a day or two. It is usually in great shape with nice tiny littles bubbles by then. It takes too damn long just setting it at serving psi and waiting, but leaving it at 30 psi gives big bubbles like soda pop. :mug:
 
attitude said:
what temp is the keg at? i am putting my belgian in the keg tonight ( maybe)
You want the beer cold.

My typical routine:

Wednesday night, rack to keg and place in kegerator to chill overnight.
Thursday morning, hook up the CO2 to 30PSI and give a good 3-4 minutes of shaking (shutting manifold valve to other kegs first). Place back in fridge and leave keg hooked up at 30PSI all day.
Thursday night, another 3-4 minute shake...set PSI back to serving and open all manifold valves.

Friday night, brats on the grill and ice cold beer off the tap. No complaints from my guests yet...

Exhibit A - Friday Night's Draw:
APA_Kegged.jpg
 
NICE. Is 37 degrees too cold. waiting for the ranco to show up so i can up the temp a little. should be here in a couple of days
 
attitude said:
Sorry im such a NOOb force carb on the gas or liquid side? thanks
No problem,

I usually don't have the beverage line hooked up yet cuz it gets in the way...FYI.

I lay the keg flat across my lap and the gas side is usually down. This way you can hear the bubbling of the gas inside as you agitate the keg (usually I shake from left to right, end to end).

When you stop shaking, you'll hear the bubbling stop. Shake it more and the bubbling starts up again. This is truly forcing the carb into the liquid. Repeat this whole thing for 3-4 minutes each of the two times you shake it.
 
thank you munch. it's in the keg put a little co2 to bleed off head space. well see what happens.
 
HELP
Is there a proven chart or calculator the gives the length of time to force carbonate at a certain temp and pressure level to achieve a particular Vol level?
 
HELP
Is there a proven chart or calculator the gives the length of time to force carbonate at a certain temp and pressure level to achieve a particular Vol level?

I don't believe there are any. I'd love to find out differently.

Brew on :mug:
 
HELP
Is there a proven chart or calculator the gives the length of time to force carbonate at a certain temp and pressure level to achieve a particular Vol level?

it has always vexed me that you can easily find the graph with pressure and temps for volumes of CO2 but nobody ever mentioned the time needed to achieve these volumes at that pressure and temp. So, for me, that chart was of very little use. I put a keg in the fridge at 30 psi for about 48 hours. then back it off to serving pressure, ~7psi, bleed it and wait another day or so. I never liked shaking the keg. it could be a mental thing but I thought it tastes different than if you leave it still.
 
it has always vexed me that you can easily find the graph with pressure and temps for volumes of CO2 but nobody ever mentioned the time needed to achieve these volumes at that pressure and temp. So, for me, that chart was of very little use. I put a keg in the fridge at 30 psi for about 48 hours. then back it off to serving pressure, ~7psi, bleed it and wait another day or so. I never liked shaking the keg. it could be a mental thing but I thought it tastes different than if you leave it still.

The reason the charts (or equations) don't exist is that it's very difficult (especially for a homebrewer) to collect the correct data from which to generate the charts/equations. Time to carb depends on the following variables (and maybe more):
  • Temperature
  • CO2 pressure
  • Initial carbonation level of the beer
  • Beer surface area exposed to the CO2
  • Volume of beer
  • Alcohol content of beer
  • Viscosity of beer? (affected by alcohol, dextrin, protein, etc. content of beer)
To collect the required data, you would have to start with beer having a known level of carbonation, and then carbonate for different time durations at a fixed temperature and pressure. After the specified time duration, you have to remove the excess CO2 pressure and allow the beer to come to equilibrium w.r.t. temp, headspace CO2 partial pressure, and current carb level. Then determine carb level by measuring the equilibrium headspace pressure (accurate to 0.1 psi at least.) After you have collected 25 - 100 data points (each time, temp, pressure measurement is one data point) you curve fit the data to determine an approximate equation for carbonation level vs. time, pressure and temperature. Each data point may take several weeks to generate.

You need a well controlled temperature chamber (i.e. chest freezer) to control the temp of the beer during carbonation. A BrewPi controller would provide adequate temperature regulation, but an on/off controller (e.g. STC-1000) probably wouldn't be adequate. You can't use your normal keezer/kegerator for temperatures other than your normal serving temps, so you probably need an additional chest freezer, unless you stop drinking draft beer while you conduct the measurements. You can only do one CO2 pressure at a time unless you have multiple CO2 regulators.

Anyone want to sign up to do this experimentation? I can help with the experimental plan and data analysis.

Brew on :mug:
 
The chart has incomplete data and thats frustrating for folks who are starting to keg and wondering how this all works. I found a system that works well enough for me through trial and error. By me, half the point of kegging is to pour a beer in less time than bottle carbing.
 
The chart has incomplete data and thats frustrating for folks who are starting to keg and wondering how this all works. I found a system that works well enough for me through trial and error. By me, half the point of kegging is to pour a beer in less time than bottle carbing.

In what way do you believe the chart is incomplete? The chart just provides equilibrium CO2 headspace gauge pressure vs. carbonation level at various temperatures. It was never intended to provide any information on timing.

Brew on :mug:
 
yeah, it doesn't. thats why its incomplete. time is a thing when force carbonating. common kegging instructions give you the chart and say set the regulator at xx psi and put the beer at xx° for x volumes co2. i suppose this is not inaccurate but the piece that is left out and which gave me grief at first was the time required for it to equalize. Perhaps I'm not learned enough to know this automatically but it never made sense to me and i think i can't be the only one. Its like fermenting. you add however much yeast but its not done for some time. most instructions estimate a week or two to finish fermentation. may be a similar estimate could be provided with kegging instructions?

May be that this is not possible to know or estimate but i think its worth mentioning, to folks who are getting started kegging and are trying to figure out best practices for their brewery, that time is a factor when force carbing
 
The table is proper as it is only intended to provide equilibrium values.
Solving "carbonation time" was never it's mission.

And as has already been stated, it is difficult to provide a table showing "carbonation time" as any calculation has to include geometric data specific to the vessel used, the beer volume and its post-fermentation carbonation level and specific gravity, and more.

It's a multi-factor calculation not optimal for 2D or even 3D tables or charts...

Cheers!
 
yeah, it doesn't. thats why its incomplete. time is a thing when force carbonating. common kegging instructions give you the chart and say set the regulator at xx psi and put the beer at xx° for x volumes co2. i suppose this is not inaccurate but the piece that is left out and which gave me grief at first was the time required for it to equalize. Perhaps I'm not learned enough to know this automatically but it never made sense to me and i think i can't be the only one. Its like fermenting. you add however much yeast but its not done for some time. most instructions estimate a week or two to finish fermentation. may be a similar estimate could be provided with kegging instructions?

May be that this is not possible to know or estimate but i think its worth mentioning, to folks who are getting started kegging and are trying to figure out best practices for their brewery, that time is a factor when force carbing

Yes time is a thing when force carbing. If you use the "set and forget" (set at the chart pressure for the current temp and desired carb level), then it will take two to three weeks to carb a full keg. With set and forget, the carbonation rate starts out relatively fast, but the more carbed the beer becomes, the slower it picks up more carbonation. (Instantaneous carbonation rate is proportional to the difference between the current headspace CO2 partial pressure and the equilibrium CO2 partial pressure for the current level of carbonation [i.e. the "chart" pressure for the current level of CO2 in the beer].)

If you use "an over pressure" method, like 30 psi for 36 hours, then set to serving pressure, you can be essentially done in about four days. If you set at serving pressure and agitate the keg, you can be done in less than an hour. Some folks even use over pressure and agitate, but these are most often the people who start threads about how to deal with an over carbed keg. :goat:

Any method that uses pressurized CO2 to carbonate is "forced carbonation." If you specifically want to talk about over pressure or agitation (shaking, rolling, etc.) methods then you should use the term "burst carbonation" or "accelerated carbonation" to differentiate from set and forget.

Brew on :mug:
 
The chart has incomplete data and thats frustrating for folks who are starting to keg and wondering how this all works. I found a system that works well enough for me through trial and error. By me, half the point of kegging is to pour a beer in less time than bottle carbing.


If your looking for speed you should consider a sintered stone. 10-12 psi through a stone will get you perfect levels in less than 24 hours and passable beer in an hour at 30 psi.

https://www.homebrewsupply.com/carb...n-stone.html?gclid=CLDShqaF8NECFcm4wAod8EQFUw
 
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