Author Topic: Head toward end of keg  (Read 891 times)

Offline brewinhard

  • Official Poobah of No Life.
  • *
  • Posts: 3225
    • View Profile
Head toward end of keg
« on: July 01, 2016, 12:30:03 AM »
Has anyone ever observed a slight fading of head retention on beers as they get closer towards the bottom of  the keg versus from the start? I am only really talking about the last 5-6 beers. And this is even when the pressure has not changed. I just find it curious. Wondering if it has anything to do with gelatin...

Offline Phil_M

  • Senior Brewmaster
  • ******
  • Posts: 1693
  • Southern Maryland
    • View Profile
Re: Head toward end of keg
« Reply #1 on: July 01, 2016, 12:50:05 AM »
Nope, usually I see the opposite. Might have something to do with my preference for flatter beers, which results in tapping the keg before fully carbonated.
Corn is a fine adjunct in beer.

And don't buy stale beer.

Offline lindak

  • Cellarman
  • **
  • Posts: 42
    • View Profile
Re: Head toward end of keg
« Reply #2 on: July 01, 2016, 04:01:17 AM »
i kicked a keg tonight.   I think the last few beers were a bit foamier.  Instead of the dense, small bubbles in the head of earlier pours, the head was more frothy.   I also noticed this on a commercial keg that kicked a week or so ago.  I had speculated that I was somehow picking up an excess of co2-- i.e., I was getting a mix of beer and co2.  Again, this wasn't just the last beer.  It was the last few beers. 

Offline brewinhard

  • Official Poobah of No Life.
  • *
  • Posts: 3225
    • View Profile
Re: Head toward end of keg
« Reply #3 on: July 01, 2016, 11:39:26 AM »
i kicked a keg tonight.   I think the last few beers were a bit foamier.  Instead of the dense, small bubbles in the head of earlier pours, the head was more frothy.   I also noticed this on a commercial keg that kicked a week or so ago.  I had speculated that I was somehow picking up an excess of co2-- i.e., I was getting a mix of beer and co2.  Again, this wasn't just the last beer.  It was the last few beers.

This sounds like what I am referring to. The head seems to be made of larger, rounder bubbles vs. the tighter foam-capping heads I am used to.

Offline beersk

  • Official Poobah of No Life.
  • *
  • Posts: 3484
  • In the night!
    • View Profile
Re: Head toward end of keg
« Reply #4 on: July 01, 2016, 12:51:45 PM »
When I used gelatin, I seem to notice head gets thinner as does the body of the beer towards the end of the keg. I've stopped using it.
It also might be a bit of oxidation towards the end of the keg too.
« Last Edit: July 01, 2016, 12:53:47 PM by beersk »
die Schönheit der bier...

Jesse

Offline brewinhard

  • Official Poobah of No Life.
  • *
  • Posts: 3225
    • View Profile
Re: Head toward end of keg
« Reply #5 on: July 01, 2016, 07:34:37 PM »
When I used gelatin, I seem to notice head gets thinner as does the body of the beer towards the end of the keg. I've stopped using it.
It also might be a bit of oxidation towards the end of the keg too.

Yeah, I am wondering if it had something to do with a smaller amount of beer being in more contact with the gelatin itself. Unsure about oxidation as I have had it happen on beers that kick pretty quickly too. But that could also play a role. Maybe head-forming proteins are getting broken down somehow along the way?

Beersk- noticed on another thread you stated you were done using gelatin.  What are your thoughts on it?

Offline blair.streit

  • Brewmaster
  • *****
  • Posts: 516
    • View Profile
Re: Head toward end of keg
« Reply #6 on: July 01, 2016, 07:51:04 PM »
I've noticed this on both fined and non-fined beers in my kegs.

I always assumed it was some difference in the type or variability of pressure exerted by mostly CO2 versus CO2 plus some hydrostatic pressure from beer above (the former being more likely to create ideal conditions for foaming).

I see similar results if I have something partially blocking the dip tube which then clears mid-pour.

Offline brewinhard

  • Official Poobah of No Life.
  • *
  • Posts: 3225
    • View Profile
Re: Head toward end of keg
« Reply #7 on: July 01, 2016, 09:52:22 PM »
I've noticed this on both fined and non-fined beers in my kegs.

I see similar results if I have something partially blocking the dip tube which then clears mid-pour.

Yes, I too have noticed it on both fined and unfined beers. You may be on to something with the hydrostatic pressure from beer above. And seeing it happen from a partially blocked dip tube makes sense as CO2 is likely being knocked out of solution.