I just did this. It was part of a competition we had and with the PB2 and Vodka I added Cherry Extract (Cherry was the contest part). I was going for a Peanut butter and (cherry) jelly beer. I didn't put enough cherry in and it really tasted mostly like vodka.
It didn't ferment for long enough...
I'm sure that wasn't it. I moved it to a secondary conditioner and got a lot of oxygen in there. If anything it was fermented too long, if that is such a thing.
Ok so I totally botched a batch. Fortunately it was only one gallon. It was a Three Floyds Rabbid Rabbit Clone which is a Saison and one of my faves.
Anyway... I think I had old yeast, it was oxidized, yield was off... etc etc...
It basically tastes like a watered down, fizzy apple cider at...
So I did wind up splitting this into three when I moved to secondary fermentation and did first dry hop additon. I split them up as follows.
1) First gallon was my control/didn't do anything to it. Got a great rack and it was super clean/clear.
2) Second I added 1 1/3 cup of corn sugar to...
Decided to just leave it. It has been humming along fine. Going to move to secondary tomorrow and dry hop. I may split it in half and do half sugar and half just leave it alone. Not sure though.