Beardbread? I've heard of that. Old polish families used to make it all the time, and it's still for sale across the world. Since it's more likely that you have one of those loaves of beardbread, than you actually have the beard of Gilgamesh in a common loaf of bread, I've going to have to rule that one out, too.
Keep looking, though. According to the savvy logicians here on 4chan /sci/, you can't actually rule out the existence of Gilgamesh, therefore his beard could be out there, somewhere.