Help! My homebrew keg froze, I brought it in, and now the beer is all foam.

Question

I had my twin corny-keg setup in the garage in a refrigerator. The fridge kept it about 34 F degrees all summer, and I had the CO2 dialed just right.

Well, it dropped down to about -5 F and my beer froze inside the refrigerator. (Not solid - but it turned "slushy")

I brought the keg inside, and it's at about 43 degrees now. When I try to pour a beer all I get is foam.

Is this just because it's too warm now? Or did freezing it affect the beer (and it's CO2 absorption) in a bad way?

Is there a way to fix this, and get my keg flowing again?

Answer 1

Freezing and thawing tends to force CO2 out of solution, but relax - the beer is probably fine. You should be able to remix the ice and beer after everything is thawed, and readjust your carbonation with no trouble. The beer should taste the same after your carbonation issue is fixed.

RDWHAHB!

And yes, the foam is likely a result of heating. For a given pressure, only around 85% as much CO2 can be dissolved in beer at 43°F as compared to 34°F. The remaining 15% CO2 is trying to come out of solution.

For the foaming, either rechill to 34° or lower the keg pressure. If you have a bleeder value on top of your keg, you can vent here; otherwise, disconnect the gas-side quick connect and bleed some pressure. Briefly vent, wait for foam to settle, and repeat if needed until you've reached the desired pressure.

As a side note, you just reinvented the eisbock. =)