Jesus NEVER taught transubstantiation, otherwise He would have never left the room alive.
What? Then he was unable to foretell what would happen to him? You know better than that.
How else to explain the visceral and final reaction of so many of his disciples to that disclosure - "this is a hard saying; who can hear it?" and many "walked with him no more". If it were only symbolic, why the horrified response and absolute rejection?