Darker beers towards end of keg

[kev]

Hi all,

I am new to kegging beer and I noticed that as I empty my kegs the color of my beers darken. I do NOT cold crash before racking from the fermenter into the kegs. What I do is: rack into keg, put keg into kegerator at around 10 psi for a day or so at 40* F, then raise co2 pressure to about 20 psi for 4 days. I am happy with the amount of carbonation. Just confused as to why the color of the beer is darker. I am thinking that it is because I don't cold crash the beer. Am I right. Any suggestions would be appreciated. Thanks
Cheers
Kev

 

[ShaineT]

Some possibilities:
-- Partial freezing
--Infection
--Heavier grain particles are in suspension towards the end
--You may be drawing in yeast making a cloudy lighter looking beer then towards the end the beer has cleared and appears darker.

 

[kev]

Hi,
Well I can rule out infection. The partial freezing intrigues me. I can't rap my head around that one when temp is high 30's to low 40's. I did find sediment on the bottom of my one keg (2 tap system). I have not quite finished the other one to know about that one. The beers are/ were slightly cloudy which I attributed to chill haze. They were bright when I racked into the kegs. The FG of both were around 1.004. So I can rule out fermentation taking place. Would cold crashing before filling the kegs help with this? Thank you.
Cheers
Kev

 

[ShaineT]

If you have the capability of cold crashing, its always a good thing but not completely necessary if you serve fairly cold. Consider cutting a 1/2 inch off the end of your dip tubes and keeping your serving temps in the low 40s.

 

[kev]

Hi,

Thank you for your input.

Cheers
Kev

 

[terrapinj]

how far into the keg are you talking? last couple gallons or last few pints?

how old is the keg usually?

 

[kev]

I just noticed a gradual darkening of the beer from start to finish. I am unsure of the exact age of the keg itself, it was given to me. The beer in the keg lasted only about 2 weeks. Beer has a way of disappearing in my house. After the keg was kicked I opened it to clean, sanitize, & refill, I noticed the bottom was covered with sediment. The beer was finished fermenting (3 weeks primary/secondary), it was bright when kegged. I think when I siphoned into the keg I might have sucked some sediment from the bottom of the carboys.

Cheers
Kev

 

[IvanTheTerribrew]

I think one thing you can do is take some photos throughout your process. 2 weeks is a very short time to go through a keg but I'm still just wondering how much of a change there is from start to finish. Maybe everyday just take a picture of a class of your beer in the same type of glass and same lighting.

Also maybe list your recipe and steps so we can see if there's something in there that could raise an idea.

 

[beerbeer95648]

I assume you purge the keg with co2 and minamize aeration diring transfer. Otherwise I wouldn't rule out oxidation. That will darken the beer over time. Does the flavor change as well toward the end? Other than that I would agree with others that as more particulate and yeast drops out, there is more light absorbed so the color appears to darken

 

[Bobby_M]

It has to be particulates clearing towards the end.

 

[kev]

I assume you purge the keg with co2 and minamize aeration diring transfer. Otherwise I wouldn't rule out oxidation. That will darken the beer over time. Does the flavor change as well toward the end? Other than that I would agree with others that as more particulate and yeast drops out, there is more light absorbed so the color appears to darken

Hi

I did not purge the keg with co2 prior to filling. Even though the color darkened, the flavor did not change. I've brewed these beers for years now, but never kegged them. They were the first beers I've kegged. I've been bottling my beer for 15 years now & just built a draft system. Thanks for the input.

Cheers
Kev

 

[Yooper]

Hi

I did not purge the keg with co2 prior to filling. Even though the color darkened, the flavor did not change. I've brewed these beers for years now, but never kegged them. They were the first beers I've kegged. I've been bottling my beer for 15 years now & just built a draft system. Thanks for the input.

Cheers
Kev

When the yeast drops out fully, the beer looks darker as the white falls out of it. It may seem pretty clear, but I bet the last few pints were even clearer (as well as darker).

 

[kev]

When the yeast drops out fully, the beer looks darker as the white falls out of it. It may seem pretty clear, but I bet the last few pints were even clearer (as well as darker).

Hard to tell. I had some serious chill haze going on as well. I just filled both kegs ( Irish Red,& Oatmeal Stout). I was careful not to "suck up" any yeast or sediment from the carboy. I did not purge the kegs with co2 prior to filling. I guess time will tell. Thank you.

Cheers
Kev

 

[daksin]

Even if you didn't suck up yeast, there were still millions and millions of cells suspended in the clear beer. As you chilled the beer in the keg, they slowly dropped out, collecting at the bottom of the keg. As they got sucked up by the dip tube, they lightened the perceived color of the beer by reflecting light as others have pointed out. Oxidation can also cause darkening- this may be part of your problem as well. Can you taste any oxidation in your beer?

 

[kev]

Even if you didn't suck up yeast, there were still millions and millions of cells suspended in the clear beer. As you chilled the beer in the keg, they slowly dropped out, collecting at the bottom of the keg. As they got sucked up by the dip tube, they lightened the perceived color of the beer by reflecting light as others have pointed out. Oxidation can also cause darkening- this may be part of your problem as well. Can you taste any oxidation in your beer?

Not that I am aware of. I have never had an oxidation problem before so I am not sure of the signs/ off flavors. Could you clue me in on that? I know that both beers tasted just fine from start to finish. Thank you.
Cheers
Kev