How to serve from a keg without so much foam

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jvend

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Hi, I usually place my beer (5 gallons) in my keg and carbonate at 30psi for a week, I mean leaving the co2 tank connected to the keg regulated at 30psi for 7 days. Then when Im going to serve my beer in glasses I turn down the regulator to 5psi and when I press the picnic faucet you literally see only foam getting out of it. After a while you begin to see beer in the glass nd when you taste it its flat. What can I do to fix this???? please help im desperate!!!
 
First you should use a chart to determine the psi for the proper volume of co2 for the style of beer you're carbonating. Not all beers are the same. So 30psi for 7 days is not always accurate.

Second, when you turn down the pressure for serving, do you also bleed off the excess pressure?

Third, you need to balance your system. If you have a small hose, your pressure will have to be very low. There's really a lot that can cause foam. Like restriction (going from a larger diameter to smaller from say a hose to a barb) temp differences from the beer and the hose (hose being warmer) etc...

http://beersmith.com/blog/2011/07/14/keg-line-length-balancing-the-science-of-draft-beer/

http://byo.com/stories/item/164-balancing-your-draft-system-advanced-brewing
 
Hi, I usually place my beer (5 gallons) in my keg and carbonate at 30psi for a week, I mean leaving the co2 tank connected to the keg regulated at 30psi for 7 days....
That will result in gross over-carbonation for most styles unless you're doing it at 65degF.

......Then when Im going to serve my beer in glasses I turn down the regulator to 5psi and when I press the picnic faucet you literally see only foam getting out of it. After a while you begin to see beer in the glass nd when you taste it its flat. What can I do to fix this???? please help im desperate!!!
Exactly what I would expect from your method.

It's easiest to carb and serve at the same pressure and temperature; 12psi at 38degF for my system, wherein I just set it and forget it. However, if I need it in a week, I will run 30psi for the first day, and then drop it to 12psi over the course of a few days, where it then stays for serving.

BTW, 10 to 12 feet of 3/16" ID beverage line is about what's required for a decent pour at 12psi.
 
Yeah, as others have stated, 30 psi for 7 days is your first problem. That's too high for too long. 30 psi can be used to burst carb and have beer that is ~75% carbonated in about 2 days; however, I would never exceed 48 hours at 30 psi or you risk overcarbonation and when that happens, you get pours like you described. The key to a properly functioning keg system is to make sure the system is balanced for the carb level you typically use. For most of us, we use 10-12' of 3/16" ID beer line, a temp of around 36-40°F, and about 12 psi for carbing and serving. That will get you good carbonation and nice pours without having to fiddle with the pressure once the beer reaches the ~2.3 vols of carbonation that is typical for most ales.

To fix your foaming issue, you need to reduce the carbonation level of the beer. The way you do this is by turning off the gas and periodically pulling the pressure relief valve on the keg several times over the course of a few days until you get good pours. Your keg is like a big bottle of soda and every time you purge the CO2 it is like removing the cap from the soda bottle. Every time you do it, the beer will lose some carbonation.
 
OP never posted beer temps for any of the stages listed. Of course, if it was cold, 30psi for a week is massively overcarbed. If it was 70F, not so bad but then there's the question of whether the keg was chilled down before lowering the pressure and attempting to dispense. Some folks mistakenly think they can carb a beer warm (they can) and then dispense that warm carbed beer into bottles (they certainly cannot).
 
OP never posted beer temps for any of the stages listed. Of course, if it was cold, 30psi for a week is massively overcarbed. If it was 70F, not so bad but then there's the question of whether the keg was chilled down before lowering the pressure and attempting to dispense. Some folks mistakenly think they can carb a beer warm (they can) and then dispense that warm carbed beer into bottles (they certainly cannot).

This ^^^^^ + 100. Temperature, pressure, time and line length (at dispensing) are all inter-related.

If the OP is trying to dispense at 5psi, it's possible that he's trying to compensate for his line being way to short and/or temp too high.

If a beer is properly carbed at 2.4-2.6 volumes for average everyday drinking purposes (not style-specific), it's hard to go wrong with 38*F, 11-12 psi and 12ft of 3/16" beer line.
 
Big Floyd, what about time? How many days with that setup?
 
No I mean on that pressure and temperature, (12psi, 38F), how many days does it take to carb great? At 2.5 carb unit?
 
Picnic taps are notorious for leaking under pressure, but when the top piece is tightened fully, it should not leak at 12 psi. If yours does, get a new one.
 
So maybe at 12psi at 38F will take 2 weeks to carb at a great level and it wont be over carbed?
 
So maybe at 12psi at 38F will take 2 weeks to carb at a great level and it wont be over carbed?

Yes and yes. Using the CO2 pressure that matches the dispensing temperature to achieve the desired carbonation level (volumes of CO2 - which is exactly the multiples of your beer volume in gas volume) once the beer reaches equilibrium it will never over carb.

Here's a great thread to read for kegging noobs. The chart alone is worth the look...

Cheers!
 
Correct. After the first week, you'll start to have some noticeable carbonation, but it will continue to increase over the next week or so until it can no longer absorb any more CO2.
 
Just one more question, if theres an equilibrium like you say,( that by the way I totally believe you )in which the beer cant absorb any more CO2 but is a good final product, why over carbonating happens?
 
Just one more question, if theres an equilibrium like you say,( that by the way I totally believe you )in which the beer cant absorb any more CO2 but is a good final product, why over carbonating happens?

Because if the pressure is greater than the desired volume, it will still accept that higher pressure and overcarb.

If you set it at 12 psi at 40 degrees, even if you leave it that way for years, it won't and cannot go higher than that. But if you set it at 30 psi, it will carb to the higher pressure.
 

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