After starting a new game all of a sudden now my little friends keep thowing out their spoiled food. Does anyone know what caused this and how to stop it? Thanks!

It's one of the behaviors that was not working in previous versions, which is why you're seeing it for the first time now. If you don't like a particular action that they're doing, you can scold them for it. It doesn't affect their food supply, so you don't need to be concerned about that.