Attenuation issues

[ZehBaron]

So today after wrapping up brew day for my Christmas ale, I was poking around in the basement and found some bottles of hefe weisse that I brewed this past May. After popping a bottle in the fridge for a few hours, I cracked it open. Only this time, it tasted a little different.

I expected it to have lost the banana/clove aroma by now, and it definitely did...but without the esters to distract my palate, it tastes *really* under-attenuated. Really cloying, almost like carbonated wort. I can only guess that I must have not noticed it before because the banana aroma was pretty huge when the beer was young.

So, what could be my issue here? My O.G. and F.G. readings were spot on, and right within the style ranges. And my fermentation definitely didn't stall; the AC in my apartment actually broke that week, so the beginning of primary got up to almost 78*F at high kraeusen. And it's well-carbed, so I would've had bottle bombs if fermentation was really that far from being finished.

My only guess is that my mini-mash temp was too high, giving me really low fermentability-- though I remember my thermometer reading 155 throughout. I also used a hop bag during this boil...maybe the circulation was really poor and affected my AA extraction?

Anybody have any better theories? I'd love to hear them!

Cheers!

 

[EoinMag]

Are you lifting the yeast back into suspension or leaving the tight cake behind in the bottle as with your normal homebrews?

 

[ZehBaron]

Hmm, good point...when they were young I was rousing the yeast in the bottle, but this time I decanted it. I'll pop another one in the fridge and see if that counters the sweetness.