Holes in Swiss Cheese

 For ages cheese makers were puzzled by the holes in Swiss cheese. Now it's believed that the holes are caused by microscopic bits of hay in the cheese. Gas molecules attach to the little bits of hay. The size and number of holes in the cheese are directly related to the amount of microscopic bits of clay. Swiss cheese of earlier times had larger and more abundant holes because there were more hay particles for the gas to attach to. Due to the increased technology, cleanliness has improved so there are fewer holes are they are getting smaller.