Thick gummy foam. Why?

I brewed a Bell’s Best Brown clone a month ago and I’ve got it in the keg now. It dispenses and foams up an awful lot, even with pressure almost nill. The head doesn’t dissipate very much at all. What causes it to have so much of a viscous, thick and sticky head retention? I used Marris Otter, Victory, 55L Crystal, and Special roast malts. I haven’t had a beer behave like this before. Any ideas why?

No f’n clue.

What is the consistency to the head?

I know this is a stupid question... are you sure that it is not overcarbonated...ie, are you sure the reading on your valve is correct?

not sure either...

hops act to coagulate proteins, lending to better head retention - but not necessarily ’gummy’. If you had a longer boil with more hops than you’re used to... that would be my only guess - you don’t really have high protein grains in there.

are there any ’off’ flavors?

So, your beer has a thick, sticky head that retains well? Are you complaining?

If you increase your dispensing line length you should get less foam in your pours.

Originally posted by artusory
So, your beer has a thick, sticky head that retains well? Are you complaining?

In my experience / experimentation, I have found that when I carbonate to lets say a higher carbonation level then I have this problem. I’m not saying over carbonating as in taste. For convenience and room I use a picnic tap on about 1 ft. of hose. This is not enough restriction to compensate. I’m not sure how to explain this in volumes, so I’ll try another approach. You carbonate at 30 psi to get your desired level and then reduce pressure on the gauge to dispensing pressure, lets say 5 psi. You then bleed pressure out of keg to match the dispensing pressure (5 psi). Lets say that the internal pressure of the beer is higher than 5 psi. Over time CO2 will exit the beer to the headspace to achieve equilibrium inadvertently raising the dispensing pressure. Now you may be dispensing at 10 or 15 psi. When at 5 psi normal foam. At 10 or 15 you get high foam.

To prove this theory, bleed your keg to just below your regulator setting and then begin dispensing immediately. You should see a decrease in foam as compared to if you just dispensed without bleeding pressure. I believe most regulators have a built in check valve that doesn’t allow pressure to flow back up the line into the regulator. This prevents contamination of the regulator, but this also prevents pressure form leaving the keg. That is why the internal pressure of the keg will increase.

This is just my experience and theory. If someone has more knowledge on dissolved gasses and how they bleed out I would be interested in hearing it.