Researchers have finally solved a centuries-old mystery: why does Swiss cheese have holes in it? The answer today is very much about maintaining the tradition, since the characteristic holes help with the marketing of the cheese. However, why was the cheese first produced with holes in it? The story, disappointingly, has nothing to do with mice nibbling away at it. The answer is, surprisingly, hay. It seems that in the early days of making the cheese, tiny flecks of hay fell into the milk during production. This is according to Agroscope, a Swiss government research institute. Holes in the cheese are commonly known as “eyes.” The term “Swiss cheese” is a generic one, and not all cheese from Switzerland, or made in the Swiss tradition, has holes in. This type is normally Emmental cheese. It is generally thought that the larger the “eyes” in a Swiss cheese, the more pronounced is its flavor. Taste aside, why do certain Swiss cheeses have holes in them?
To arrive at this conclusion, researches took multiple computerized tomography (CT) scans of Swiss cheese from samples.
Discovery Magazine reports that the researchers found that altering the number of hay particles in milk affects the number of holes that appear in the cheese.
Today milk is filtered through specialized milking machines, which means that it is not exposed to the barn’s open environment. This means that the holes need to be made using ‘artificial means’, and this allows Swiss cheese makers to market their distinctive products.