Beer soured then got better?

[Josephryanevan]

Hello,
So I brewed a vanilla porter before Christmas. It was tasting fantastic when I took readings etc. Then, right before bottling, it got a bad sour taste. I then educated myself on the properties of Star San and learned that mine was probably no longer effective. So I'm guessing my beer got infected.

I'm still drinking the beer because I believe that waste is sin, plus it isn't terrible. And all of a sudden after about 5 or 6 weeks in the bottle, the sour flavor mellowed. Now it's smooth and the vanilla and roasted flavors come through nice. The sour isn't gone entirely, but it's a whole different beer from two weeks ago.

What happened? I'd love to know what he opened to make that happen.

Thanks for any input.
Joe

 

[pvpeacock]

I'm curious to read the responses. I have 3 kegs full of infected beer (1 saison, 1 stout and 1 IPA). I brewed the three batches in rapid succession in 2 different conical fermenter and did not realize I had an infection in the first until it was too late for the last 2 batches. All 3 had pellicles floating on the top when I kegged them, but the gravity samples tasted fine. The stout was a little fruity/sour, but not bad. I'm curious how long I should age these kegs before I taste them again.

 

[RM-MN]

Wild guess only. It couldn't be an acetobacter infection as those only get worse nor is it likely to be lacto as that should take time to get to the sour stage. My guess is that you perceive acetaldehyde as a sour where most people might think of it as green apples. Yeast can eliminate that in the bottles.

 

[Miraculix]

Pellicle in top can mean brett, which doesn't have to be a bad thing, but it will continue fermenting the leftover sugars very slowly. This means the beer will most likely continue to change its flavour and there is a high risk of overcarbonation. For that reason, beers which are additionally infected with brett are left for months or even years in the fermentor to fully ferment. So monitor your beers carbonation level!