Spoiled sour

[DannyW]

This is my lambic at 20 months:

This is my lambic at 22 months:


It's not a trick of the light, this is really pretty accurate to how it looked/looks. It went from brilliant gold to murky dark brown just that fast. Before it had a thick leathery pellicle; that has now either dropped or dissolved. Still smells the same, like lambic. Haven't tasted it yet as I need to bring in some racking equipment to do so. It's been sitting in the climate controlled computer room at work.

Any ideas what could cause such a drastic change so quickly?

[jwatkins56550]

Did you get drunk one night and add some sinimar and forgot about it??


...Never seen anything like that..

[straight cash homey]

did you piss off anyone at work who may have farted in it as retribution

[brewinhard]

Yes. That my friend is a brewer's dreaded nemesis = OXIDATION. I am gathering this notion simply b/c you mentioned that the pellicle has dropped out. It appears that there is quite a bit of headspace above the beer and you are using a foil "airlock" which allows all sorts of oxygen into your carboy. The pellicle has saved your beer up until a couple mos ago as pellicles form in response to oxygen absorbed into the headspace. As soon as that pellicle dropped the beer started to oxidize and become darker. Next time use a carboy cap or stopper and airlock to minimize this. Depending on if the beer tastes stale, then you might be able to use it to blend into other beers to increase the acidity or flavor.

[DannyW]

Thanks brewinhard, that makes some sense. I used the foil figuring I would never be able to keep up on keeping an airlock full for 2 years, and that unchanging foil with a rubber band around the neck was better than an airlock that might sit empty for a while.

The only thing that happened between good time and ugly time was that I pulled one bottle out to take to a club meeting. The siphon was as sanitary as any other racking, and I used my little 12g CO2 injector to squirt in the headspace after pulling out the siphon. Perhaps that was not enough, and that but of O2 was the final straw.

FWIW on the same day this beer was brewed we did several batches. One of them sat for the same 20 months or so in a plastic bucket at room temp with tape over the airlock hole. It was golden and beautiful and not overly acetic when it was kegged at 20 months. Now I wonder if racking, even to a purged keg, was enough to tip that one too. Must pull samples and see!

[straight cash homey]

i don't know about that explanation, I still think it's farts. did you smell it yet?

[boobookittyfuk]

does it taste like vinegar?

if not, then it probably isn't oxidized.

what yeast(s) / bacteria did you use to make this thing?