Fishy Taste/Aroma?

[VladTheImpaler]

So we brewed a stout a few weeks ago and yesterday we went to transfer from fermenter into a keg and the whole thing smelled like fresh fish... I went to taste it and it tastes nice and roasty with coffee notes like a stout should... only it's followed by fishiness.

Nothing went wrong during brew day, it didn't show any signs for an infection, all seemed perfectly good and well.

The only thing I'm thinking is that it's the yeast we used. We used Windsor dry yeast which is one that we haven't used before.

Has anyone else ran into this issue before?

I'm hoping the aroma and taste go away with cold crashing but feel free to enlighten me on the situation if I just need to dump it and start over with a different yeast.

Cheers!

 

[ong]

I would maybe try off-gassing more than usual during carbonation. It sounds like some kind of ester aroma from fermentation — how warm did you ferment? Also, water could be a suspect. (I would say autolysis but that doesn’t seem likely given what you’ve described.)

 

[VladTheImpaler]

I would maybe try off-gassing more than usual during carbonation. It sounds like some kind of ester aroma from fermentation — how warm did you ferment? Also, water could be a suspect. (I would say autolysis but that doesn’t seem likely given what you’ve described.)

I'll just keep purging the keg with CO2 as it sits and see if that makes a difference.

We fermented between 68-70, same as all our other beers. And it's the same water we used for all our others beers. All variants were the same as with our other brews, yet this is the only one that has experienced this aroma. That's what led to me thinking it could be the yeast. It's the only variable that we really changed from usual.

I suppose that the water could have been different that day? But even still I've never heard of less-than-optimal water making beer taste and smell fishy... but I guess it's not impossible.

 

[ong]

I’ve not had good experiences with Windsor, although I haven’t gotten that flavor (mostly excessively fruity/low attenuation). I suggested water because I thought it might have had the flavor going in. But it sounds like you don’t have a lot of variables.

I’ve definitely gotten some soy/umami from some stout grists, but I don’t know if that could read as fishy.