Could you feed piranhas chicken hearts rather then beef hearts?

I have been feeding my piranhas those little beef heart pellets you get frozen at the pet store and now that they are getting bigger, i believe that they should have something a little bigger. Now i know a lot of people feed piranhas full beef hearts and feeder gold fish but i was wondering if it would be safe to feed them chicken hearts as they are a whole lot cheaper and very easily obtained. So are chicken hearts safe for piranhas to eat?