The Truth

Why does Swiss cheese have holes in it?

The TruthMarch 23, 2001

Dear Cecil:

Why does Swiss cheese have holes in it?

— Cassie, via America Online

Cecil replies:

No one wants to face up to this squarely, so I guess it’s up to me. Swiss cheese has holes in it because of bacteria passing gas. Contemplating a typical piece of Swiss cheese, the majority of whose holes, by USDA regulation, must measure between 11/16 and 13/16 of an inch in diameter, you may think: Here was a little microbe with a serious case of indigestion. But actually it’s the work of armies of microbes, specifically Propionibacteria shermanii. The P. shermanii consume the lactic acid excreted by other bacteria (the ones that cause the milk to turn into cheese in the first place) and belch, toot, and otherwise exude copious amounts of carbon dioxide gas. This produces what the Swiss-cheese industry, hoping to distract from the reality of the matter, calls “eyes.” It’s a beautiful, natural process, with the advantage that it enables cheese makers to charge good money for a product that by law is partly air.

But the air/cheese ratio will be changing soon. It seems Swiss cheese with big holes fouls up modern slicing machinery. So the industry is now asking that the regulations for Grade A Swiss be revised to make the average hole only three-eighths of an inch in diameter — one-quarter the area it is today. (Small-hole Swiss is now classified as Grade B, which commands a lesser price. Libertarians, needless to say, are frothing at the very idea of the government regulating Swiss cheese hole size.) For many it just won’t be the same. One nudnick on the Internet, showing the effects of too much consumer brainwashing, claims the best part of Swiss cheese is the holes: “If only there were more holes and they were bigger”! Come over to my house, bud, and I’ll sell you some cheese that’s all holes. The rest of you can console yourselves with the thought that you’ll be getting more cheese and less thin air.