The male fertilizes the eggs with their papilla, that's located between the anal and ventral fins. Not his mouth.
Is he actually eating the eggs, or is he blowing on them? Blowing on them is normal.
If they are not the only fish in the tank, it isn't uncommon for the angels to eat the eggs because they would rather do that than see them eaten by others. Most people that want to get into breeding will keep the mated pair alone, some go as far as removing the eggs or the angels into separate tanks. if separated though, steps have to be taken to keep the eggs from growing fungus.
If left in a community aquarium though, it won't be too common to get and keep fry alive (very many at least).
Angelfish also will need to spawn a few times before they get it 'right'.