Possible Mold Issue?

[Boyd]

I just kegged a Negro Modelo copy that has a taste that is somewhat acetic, similar to nail polish (not nearly as harsh). I noticed some very small black dotting throughout the open space in the carboy. Am I contaminated?

I've tried to take a few pics of the carboy, but the black dots aren't showing up well enough to see.

 

[Jwood]

if it truly does taste like nail polish (more like nail polish remover?) it very well could be Ethyl acetate. What is your process? Yeast wise and fermentation wise to be specific.

 

[Boyd]

1hr steep @ 152*F. 1hr boil. 3 oz Saaz @ 0, 30, 60. Pitched San Francisco Lager @ 70*F. Let ferment at 58*F for a month.

On second look, the mold issue was on the outside of the carboy, not on the inside. It does taste a little acetic.

 

[Jwood]

thats a little high to pitch that yeast. How did you cool down the wort after pitching? Fermentation chamber? cool basement?

Pitching high and then cooling down can really stress out the yeast. In addition with lower temperature fermenting yeast, fermenting high can also create all sorts of problems.

Also did you pitch enough yeast? You need about double the lager yeast as you would ale yeast for a similar sized batch.

However, it could still be ok. Since it is a lager, if you condition this cold for a month or more, you may just find that the flavor has significantly subsided.

 

[NordeastBrewer77]

how big of a starter did you pitch? are you lagering this?