Blue cheese is actually molded cheese! It gets its ‘blue’ by adding a chemical called Pennicillum Roquforti to the milk and to the rennet mix. Typically after the cheese is formed cheesemakers will push very thin spikes through the center. This allows air into the mixture so that the cheese may fully form. Technically, because of the fact that cheese makers add mold to the cheese itself, blue cheese is not a molded cheese by nature, but it is a man made molded cheese.