acetaldehyde problem?

[bbksv]

So I brewed a Caribous Slobber all grain kit from NB as my first brew with my grainfather. I am kind of at a loss as to what might have caused my off flavors. I brewed it right in accordance with the directions as far as mash and everything goes. Everything went well...used the counterflow chiller and got it down to probably 66F before pitching yeast (danstar windsor ale dry yeast)

I let it ferment for a week and checked gravity which was about 1.018 (down from OG of 1.052) and then let it go for another couple weeks. I was doing some other brews..meade and wine and had some energizer out so threw a pinch of that in as well. I was out of town for a while and just let it go for 2 weeks. FG was 1.015 and just transferred to a keg.

Fermentation temp was only like 68F. The 1 packet of dry yeast should have been enough for a 1.052 brew. I am also pretty anal about cleanliness so I don't think it is a infection.

Any ideas on what might have caused it? Think it is salvageable?

 

[brewery_fixer]

Did you proof the Yeast?

 

[bbksv]

Yep....let it sit for an hour or so vs the 15 min it asked for though.

 

[bbksv]

It actually tasted great at that 1 week mark..when it was 1.018

 

[RM-MN]

Yep....let it sit for an hour or so vs the 15 min it asked for though.

Don't do this on the next batch. The yeast do best if rehydrated but after 15 minutes all the reserves will be used up and the benefit of rehydrating begin to be lost so after an hour you may not have as much good yeast as you started with.

Acetaldehyde is a natural byproduct of fermentation and the yeast will clean it up given the right conditions. When the yeast activity slows, warming the beer a bit may be all it takes to get that done.

 

[dmtaylor]

What makes you think you have acetaldehyde? That off-flavor is very rare compared to many other things. Also, there is a big difference between the green apple flavors of acetaldehyde versus red apple which is esters.

Also I have to ask you to reconsider the possibility of contamination. Windsor ale yeast doesn't attenuate to 71%. It just doesn't. More like 62% or something like that. If your beer fermented down to 1.015, that ain't Windsor I don't think.

 

[bbksv]

There is a definite green apple flavor but maybe there was some contamination......

I just started a wine this morning and I was about to blast it with a shot of O2 and there was a little black spot on my diffusion stone so there is a possibility there was a bug from there that got into the wort when I oxygenated it.