Beer discoloration over time

[mezzoblue]

An issue I've increasingly noticed since I started all grain brews about 6 months ago is that the beer I now make ends up changing color over time as it bottle conditions, maybe picking up 3SRM or so as it darkens over the course of a few months.

That part I can handle, but what I don't like is how the beautiful rich colour the beer starts at goes murky and very dull over time. A brilliant golden yellow turns to dingy faded khaki. A deep reddish amber will go football brown.

Anything in particular that might cause this that I can look out for in my process / ingredients?

 

[Suthrncomfrt1884]

The only think that should effect your color is the settling yeast. The yeast will reflect light and cause your beer to look a little brighter. As it settles out, the beer will change color. I would think this would cause it to be clearer though, and not murky.

Is this happening while the beer is cold, or all of the time?

 

[mezzoblue]

Hard to say. I think it's all the time, but I'm not in the practice of cracking warm bottles. It's a good point though, maybe chill haze has something to do with it. Could I expect a colour shift from chill haze alone?

 

[Suthrncomfrt1884]

Hard to say. I think it's all the time, but I'm not in the practice of cracking warm bottles. It's a good point though, maybe chill haze has something to do with it. Could I expect a colour shift from chill haze alone?

No, it shouldn't cause a color shift...but it would make your beer look a little murky.

 

[dcp27]

oxidation can darken a beer

 

[ChillWill]

I work in a bar and notice the beer coming out the end of a cask is noticeably darker than when it was freshly tapped.

 

[Germelli1]

Do you notice any flavor degradation as well? Oxidation can cause colors to change over time. Not saying it is the reason here, just brainstormin a bit!

 

[ChillWill]

The flavour is better at the start yeah, but the beer at the end isn't bad, it has usually just lost some hop aroma and on very rare occasions if it has been on for a while it'll be a bit stale.

Shouldn't be too much of a problem in bottles unless they're really old.

 

[mezzoblue]

I suppose it could just be oxidation. I'm normally pretty careful to avoid it, but it's impossible to eliminate completely. If that's the cause, I'd expect a lot more people on here to have this same problem but I didn't see any when I searched for the issue before posting.

 

[Rip]

That's an odd little mystery you have there - maybe you could tell us more about your recipe(s) and process?

Beer 'shelf stability' is something that lots of folks have seriously studied. I'm sure there's some bit of info out there that would give us a clue.
As a matter of fact, my mind is tugging at my shirt trying to remind me of something I read about beer stability... lost in the fog I fear. Anyhow.

Do you vorlauf?

Do you use any kind fining agents?

Describe your bottling procedures?
How are you carbonating?

Are you storing the beer someplace extra warm maybe?

..just putting stuff out there and trying to be helpful

- M

 

[mezzoblue]

Yeah, process notes might help. Recipes are mostly from Brewing Classic Styles, so that's probably not the issue, though I suppose ingredients might be. Most of my supplies are fairly local within British Columbia, Gambrinus being the maltster where my base grains come from.

Due to limited space and no outdoor access, I do BIAB on my home stove, with a 20 minute dunk of the bag in a secondary pot for sparging. No vorlauf is possible with my system. I end up with a ton of flour in the brew pot, though after whirlpooling I tend not to transfer most of it as it nicely settles into the trub.

Fining is strictly irish moss in the boil. Bottling involves racking to a bottling bucket, then filling each bottle by hand with a bottling wand. Carbonation is priming with dextrose, no added yeast. Temperature might be part of it, I'm limited to room temperature storage.

Hopefully some of that triggers whatever latent thought you thought you might have had!

 

[Rip]

I'll need to take an educated guess here but I'm sure the lack of vorlauf can contribute to 'colloidial instability' - aka beer changes. You see, as a beer gets a little older it can start to notice girls... oh wait, wrong lecture.

Seriously though; higher level of polyphenols can increase the beers sensitivity to oxidative changes. In other words, the extra stuff that doesn't get filtered during spargeless brewing might be your biggest suspect.
I've seen reference to using Polyclar as a fining agent to help get tannins and related compounds to precipitate before bottling. This might be a cheap fix to help get added stability?

I'm all about cheap & easy brewing (its fun right?) but this situation could be one of the problems that are inherit to using a modified brewing process (BIAB). I'd be curious to hear others experience with BIAB to see if anyone else has noticed color and/or clarity changes in bottled BIAB brews vs. expected shelf life for 'sparged' homebrews.

ps. I've tried Polyclar in a few of my earlier AG brews without any problems. I just happend to have some in my cupboard from a wine related adventure. Or fiasco = I don't like wine. :cross: