I made a 400ml starter from the dreggs of jolly pumpkin La Roja and Noel in a 1000ml flask. No stirring. I left it about a month, mainly because I wasn't sure which beer to add it to. It had a nice pellicle.
I decanted it because I'm concerned about acetic acid from exposure to 02. I pitched it into an already sour beer, my Bruin. After decanting, I tasted the pour off and it was insanely sour. Much more than anything I've ever had from Cantillon, RR etc. It was actually largely unpalatable, and my fear is that this is from acetic acid (vinegar taste). It didn't taste like vinegar to me, but I also don't really trust my palate enough to make that call.
Should I worry about this in the Bruin which has already been through primary?