snail59
Regular.
Is the secret pressure or temperature??.
Force Carbonating in a Corni.
- Thread starter snail59
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31bb3
Landlord.
Pressure
snail59
Regular.
What Pressure would you recomend Eddie. Got mine at 35psi at the moment. Only been in since tuesday but pored a glass to see if tap works. Came out with a great head but no real carbonation in the beer.
31bb3
Landlord.
you need to gas to about 50psi then shake it vigorously till the pressure drops then regass but you only need about 5psi to dispense
snail59
Regular.
Thanks mate will go up the pressure and have a shakeing session 
31bb3
Landlord.
have you got a pressure gauge just shake it for now with the pressure you have in then you can add a bit more gas and shake it again then try dispensing
Can I suggest that unless you want a glass of foam, you don't go any higher than 20 psi when you are force carbing . . . it is all to easy to overdo it. Unfortunately it does mean that you have to shake longer. . . . also keep the pressure constant for carbonation (@ equilibrium) and serving increasing and decreasing the pressure will cause fobbing in the lines . . . and pints of foam.
snail59
Regular.
You can suggest what you like Tony wether we listern is another matter :lol: :lol: .So what your saying is gas to 20psi leave C02 conected and set gauge to 20psi with valve open shake like ive never shaken before but then leave at 20psi to serve.
Guys . .. What you have to remember is that the amount of CO2 that will dissolve into a liquid is dependant on 2 things. The pressure applied to the gas, and the temperature of the liquid. If these two things remain constant then eventually the amount of CO2 in the liquid phase reaches an equilibrium. The intent when force carbonating (Using higher pressure/shaking) is to help reach this equilibrium point much faster . . . Now how much CO2 you want in your beer is a matter of personal preference but The formula to determine the pressure (P) you need to set for any temperature (T) to get V Volumes of CO2 in the beer is
Where P is Pressure in PSI
T is Temperature in Fahrenheit (I pinched it from a US site )
and V is Volumes Of CO2
Real Ale has between 1.0 and 1.5Vols of CO2
Lagers have 2.0 - 2.5 Vols
Belgians is around 3.5+ Vols
So If we have a beer at 20C and we want 1.2 Vols of CO2 we need to Set 7psi on the regulator, and then let the beer reach equilibrium (usually around a week) . . . To speed this up as I mentioned earlier we can do two things
1) Shake the beer - which really means rock it backwards and forwards in your arms. While doing this you can hear the CO2 bubbling in . . . eventually it slows and stops . . . the beer is now at equilibrium and you should have perfectly carbonated beer. Shaking at the set pressure is a bit of a slow way of doing it, and my attention wanders, however you will not over-carbonate your beer this way.
2) Increase the pressure and shake . . . by cranking the pressure up to two, three or four times the desired equilibrium pressure you can increase the speed at which the liquid dissolves . . . unfortunately this is not a controllable method, and it is all too easy to over-carbonate your beer. What I do if I use this method is to shake for 100 shakes (or 30/60 seconds) then check carbonation . . . if it needs more try again, until eventually I have the desired (or just under) carbonation level I want.
The final step is to release all the pressure in the keg turn the regulator down to the set pressure and then serve at that pressure. Note that this will not guarantee that you will not get foaming beer when you try to serve it. The final phase of all of this (And it applies to naturally carbonated beer as well) is to balance the dispense set up so that the resistance of the beer line drops the apparent pressure at the open tap to as near as 0 psi as possible . . . that way all the CO2 stays in the beer. This is where the choice of dispense line (3/16" over 3/8") and length becomes important . . . Even with a flow control tap if you balance your lines first and then use the flow control to fine tune, you will get a better pour, than trying to just drop the pressure with the FC tap.
One word of caution, force carbonating a beer does introduce a change in the taste of the beer . . . some say it is a harsh metallic taste . . . it is not something to worry about as it does fade with time and I would bet that if you force carbed (with shaking and pressure) a keg and allowed another keg of the same beer to carbonate slowly (either with top pressure or using natural carbonation) after two weeks you will not be able to tell the beers apart.
And snail yes you can pressurise and serve at 20psi . . . which for a beer at 20C will generate 2.0Vols of CO2 . . . More like bottled ale or getting into lager territory . . .. and make sure you have balanced lines or you will still get froth :lol:
Code:
P = -16.6999-(0.0101059*T) + (0.00116512*(T*T))+(0.173354*(T*V)) + (4.24267*V)-(0.0684226*(V*V))Where P is Pressure in PSI
T is Temperature in Fahrenheit (I pinched it from a US site
)and V is Volumes Of CO2
Real Ale has between 1.0 and 1.5Vols of CO2
Lagers have 2.0 - 2.5 Vols
Belgians is around 3.5+ Vols
So If we have a beer at 20C and we want 1.2 Vols of CO2 we need to Set 7psi on the regulator, and then let the beer reach equilibrium (usually around a week) . . . To speed this up as I mentioned earlier we can do two things
1) Shake the beer - which really means rock it backwards and forwards in your arms. While doing this you can hear the CO2 bubbling in . . . eventually it slows and stops . . . the beer is now at equilibrium and you should have perfectly carbonated beer. Shaking at the set pressure is a bit of a slow way of doing it, and my attention wanders, however you will not over-carbonate your beer this way.
2) Increase the pressure and shake . . . by cranking the pressure up to two, three or four times the desired equilibrium pressure you can increase the speed at which the liquid dissolves . . . unfortunately this is not a controllable method, and it is all too easy to over-carbonate your beer. What I do if I use this method is to shake for 100 shakes (or 30/60 seconds) then check carbonation . . . if it needs more try again, until eventually I have the desired (or just under) carbonation level I want.
The final step is to release all the pressure in the keg turn the regulator down to the set pressure and then serve at that pressure. Note that this will not guarantee that you will not get foaming beer when you try to serve it. The final phase of all of this (And it applies to naturally carbonated beer as well) is to balance the dispense set up so that the resistance of the beer line drops the apparent pressure at the open tap to as near as 0 psi as possible . . . that way all the CO2 stays in the beer. This is where the choice of dispense line (3/16" over 3/8") and length becomes important . . . Even with a flow control tap if you balance your lines first and then use the flow control to fine tune, you will get a better pour, than trying to just drop the pressure with the FC tap.
One word of caution, force carbonating a beer does introduce a change in the taste of the beer . . . some say it is a harsh metallic taste . . . it is not something to worry about as it does fade with time and I would bet that if you force carbed (with shaking and pressure) a keg and allowed another keg of the same beer to carbonate slowly (either with top pressure or using natural carbonation) after two weeks you will not be able to tell the beers apart.
And snail yes you can pressurise and serve at 20psi . . . which for a beer at 20C will generate 2.0Vols of CO2 . . . More like bottled ale or getting into lager territory
. . .. and make sure you have balanced lines or you will still get froth :lol:
