What Makes The Holes In Swiss Cheese?

As a kid, you may have been told cute stories that the holes in Swiss cheese are made from mice, or other goofy tales. In reality, this holes, known as eyes to cheese experts, are made from the expansion of carbon dioxide in cheese. The process for turning milk into cheese complex, and each type of cheese is a little different from its cousin. So what makes Swiss cheese have these eyes where other cheeses do not? It is all about the process, and Swiss cheese is very special in that regard. Here is a look at what makes Swiss cheese different from the rest.

From Milk To Swiss

All cheese starts off as milk, and like most other cheeses in America, Swiss is made from cow’s milk. To this milk, bacteria is added in controlled amounts. The bacteria eat away at the milk, turning certain portions of it into lactic acid. This is the case for all cheeses. What is different about some cheeses, like Swiss, is the type of bacteria that is chosen for the process. Bacteria S. thermophiles, Lactobacillus and P. shermani are what are used to make Swiss cheese, and the levels in the milk must be very specific in order to make the perfect cheese. There are even some regulations on the hole sizes in Swiss cheese, making even more important the bacteria levels are perfect.

Special Combinations

As the bacteria eats away at the remaining portions of sugars in the cheese curd stage, these bacteria become particularly gassy. They expel carbon dioxide, which expands pieces of the cheese outward, making the eyes in the final product. But Swiss cheese is not the only place where these holes are evident, it is just the most pronounced. If you look carefully at a wheel of rind-less cheddar, you can see tiny holes there as well. This happens to all cheeses, Swiss is just special because it is the most common with these bacterial combinations.

Swiss Facts

This combination also gives it the special flavor. As with any cheese, it comes in several age stages, from baby to aged. As it becomes more aged, these pockets of released gas can become larger. Some cheese packagers may exaggerate these eyes for effect as well, but real, fresh swiss usually has holes from about three-eighths to eight-sixteenths of an inch in diameter. Swiss also changes flavor considerably as it ages, arguably more than cheddar or provolone cheese.