so the mice in cartoons have places to hide from the cats when they are eating it :bigsmile:
seriously though it is as Titch said due to the bacteria which exude carbon dioxide gas that makes the holes.
It is only certain kinds of cheese which have the holes; most types are from Switzerland but they occur in other parts of Europe.
Perhaps reason you may see these kinds of cheese more often in cartoons is that in the early days of cinema, the sort of people who had the skills to make both cartoons and live action films were very often immigrants from Switzerland and Germany – and when animators were asked to draw a cartoon scene where there is a block of cheese featured they would just draw this type of cheese without thinking of it..
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