I have a black plastic fermenter that I've come to call my favourite. I know what pellicle looks like and have had it and dealt with it in the past, also know what O2 can do to a beer. From the best I can remember the last brew and this Cooper's extract Cervesa I kegged a few days ago, were in the same fermenter. I tasted it this is arvo and the same bloody taste has emerged, All I can think is it is the same fermenter over 4 batches. I had a wheat I used Saf WB-06, and a lager using Saflager34/70 and now this one, using US-05. They all taste the same, exactly the same. not a vineger taste, not exactly a slick butterscotch taste, but similar to a butterscotch, like a bourbon in a way. Sweeter not really bitter.. It's not under fementing or green beer, no obvious infection in the fermentations. I don't know what it could be, I've kegged them all, just used a picnic tap thinking it might be the lines somehow, but no, the taste is still there. At first I blamed Saf WB06 and Saflager 34/70, but realise old favourite US-05 was just used .. infection ? I don't know enough about infections to classify it. maybe time to turf this fermenter?