In the movie, "Exodus," someone is able to smuggle gunpowder to a comrade in prison by baking it into a loaf of bread; the gunpowder is contained in small metal containers, not mixed in with the bread dough). My question is, would gunpowder baked into bread this way explode in the oven while baking? My followup question is, if gunpowder won't explode in these circumstances, what other explosive substance might? Thank you.