Why Swiss cheese has those mysterious holes -- as explained by a cheese expert

Why does Swiss cheese look like that? What's with all the holes? It turns out, those holes are key in making cheese Swiss!Dr. Michael Tunick, author of "The Science of Cheese," explains what goes into these bubbles. Following is a transcript of the video. Swiss cheese, those types of cheeses, have holes in them which are known as eyes because they are made to produce them. My name is Michael Tunick, I am a research chemist for the US Department of Agriculture. I wrote the book "The Science of Ch...