Serving Pressure

[miafunk2003]

Need some help regarding carbonation. Im part of a local Miami homebrew club and we do some local beer festivals. When its time to keg my beer i set it to 25-30 PSI and let it card up in a 60 degree walk in cooler. I know it should be colder but cant get it any colder until I invest in a keezer. Now when i go to the fest and put it on ice i lower the PSI to about 10-15 PSI to serve but i start to notice as the night goes on my beer is losing more and more carbonation. How can i fix this and why is this happening?

 

[br1dge]

As it gets colder, then beer should absorb more of the gas, but that doesn't explain what you are experiencing. I cant imagine it losing carbonation over the course of just a day- I assume you have it on gas when you are serving?. The best way to do it is to just set your pressure (in the 60 degree walk-in cooler) to your final carbing/serving pressure, and let it sit for 3 weeks.

 

[audger]

When its time to keg my beer i set it to 25-30 PSI and let it card up in a 60 degree walk in cooler.

for how long?

 

[miafunk2003]

For a week or two.... It's not losing all of it carbonation but it definetly decreases a lot . My guess as to why this is happening is due to the decreasing the pressure from 30 to 10 the gas starts to come out of solution. Could this be it?

 

[Brewnoob1]

So you leave it at 30psi for 1-2 weeks?

 

[miafunk2003]

Yes

 

[GilaMinumBeer]

Yeah. It's degassing. At 30psi for 1-2 weeks you are approachiing near 3 vols (2.92 @ 60*F) of co2.

 

[miafunk2003]

How can I prevent this? I don't thing breweries carb their beer at serving temps so how do they not lose carbonation when their kegs get tapped?

 

[GilaMinumBeer]

How can I prevent this? I don't thing breweries carb their beer at serving temps so how do they not lose carbonation when their kegs get tapped?

1. They don't carb at 30 psi for 1-2 weeks.

Often times they carb in brite tanks and package from that or, they carb inline.

2. They carbonate at serving pressure.





Why wouldn't a brewery carbonate at serving temp?

There are charts to determine what pressure to have at what temp to get the desired vols. Sure, you can carbonate at 20psi and 60*F but, you also have to know what serving pressure to set in order to keep the beer carbonated at your desirted vol.

The easiest, and most consistent, way to do this is to set-it and forget it.

 

[audger]

carbonation is a function of temperature and pressure. if you want to keep the same carbonation level, you will need to increase pressure as temperature increases.

http://www.classhomebrewers.org/wp-content/uploads/2011/01/Force-Carbonation-Chart.gif

like gilla said- at 60 degrees and 30psi, you are carbonating your beer to around 3 volumes. if you want to keep 3 volumes of carbonation at a lower temperature, say 35 degrees, you need 14-15 psi. if you do that, your carbonation level will not change.

if you are doing that, then there is no reason why carbonation level should change... it could just be a case of an uncalibrated tounge.

I don't thing breweries carb their beer at serving temps

they do. but it sholdnt matter the temperature as long as you follow the carb chart.

 

[miafunk2003]

carbonation is a function of temperature and pressure. if you want to keep the same carbonation level, you will need to increase pressure as temperature increases.

http://www.classhomebrewers.org/wp-content/uploads/2011/01/Force-Carbonation-Chart.gif

like gilla said- at 60 degrees and 30psi, you are carbonating your beer to around 3 volumes. if you want to keep 3 volumes of carbonation at a lower temperature, say 35 degrees, you need 14-15 psi. if you do that, your carbonation level will not change.

if you are doing that, then there is no reason why carbonation level should change... it could just be a case of an uncalibrated tounge.


they do. but it sholdnt matter the temperature as long as you follow the carb chart.

Thank you so much this makes sense now.