Head gone after chilling

[Reidman]

I have an IPA that's been in bottles for nearly three weeks at 68-70' constant and it tastes great. At room temp I can pour a nice pint with a nice two finger head and it laces the glass down to the last drop albeit it's pretty warm.

After chilling in the fridge to around 40-45 degrees the head must go south for the winter. It's non existent and I know I have good carbonation. How would chilling the beer cause it to lose it's head?

 

[Evan!]

Cooler temps equal more subdued fizz. If I opened one of my witbiers warm, it would gush...but cooled down, it didn't so much as bubble. I don't remember the chemical explanation, but I'm sure someone here does.

 

[vasie]

If I had to guess, I would say that it is because when liquids are colder, they can retain more co2 in solution. This is the same principle that applies when setting the pressure on your kegging system. So when pouring warm beer, the agitation of the pour will bring the co2 out of solution and generate a nice head. And, when pouring cold beer, the co2 is still quite soluble and is less likely to come out of solution leaving little head. When pouring from my tap, I always pour half the beer down the side of the glass and then pour the second half directly on the bottom to encourange a nice head. Everyone else agree?

 

[mlee0000]

i agree, i do 2/3 down the side, then 1/3 right on top.