Paint that my dog won't eat?

I have 2 dogs, 1 boy and 1 girl. They are both 7 months old. When they are separate they usually don't do this, but when they are together they do... they eat holes in the walls. They dig and bite into the dry wall and leave holes. My gf and I are going to patch up the holes and repaint, but do you know of any paint that the dogs won't eat? Or any suggestions? We already tried using bitter apple spray.. thanks!!