I've got Alto Wine in my inventory that's apparently flagged as a quest item. I can't drop it, and I can't drink it, and every time I pick up another Alto Wine (which I now dread) it adds another 0.5 units of weight I can't get rid of. I even went so far as stealing a bottle of Alto Wine and having the guards confiscate my stolen property to try to get rid of it - no luck.
Is this a bug, or is it actually for a quest? Which quest? I'd like to get rid of this.