I've always enjoyed eating cheese. Just getting that out of the way. I've never quite figured out why Swiss Cheese has holes! I mean, I can understand different shapes like round, square, triangular - though I can't quite fathom why swiss has holes, how they get there, etc

2 Answers 2


Those are called "Eyes" by cheese makers. The appear when bacteria convert lactic acid into propionic acid and carbon dioxide, or metabolise citrate.

These bacteria occur in dairy products, though they can also be added to the curd to get the characteristic eyes. See for example Propionibacterium freudenreichii on Wikipedia.


I don't know where this myth come from but there are no holes (or really tiny ones) in the majority of Swiss cheese:

Most famous ones :

  • 1
    Okay, so I wasn't aware that there were multiple "Swiss Cheese" for the sake of my question we'll go with Emmental which appears to be "Common grocery store swiss cheese" Dec 11, 2010 at 15:43
  • 7
    Emmental is Swiss Cheese in North America. Just like American Cheese is that horrible bright orange processed nasty stuff even though there are hundreds of different cheeses (such as the wonderful Oka) in North America. Dec 11, 2010 at 17:48
  • I visited a Gruyère factory in Switzerland once, the smell is intense.
    – Orbling
    Dec 11, 2010 at 18:47
  • 3
    Real Gruyere hasn't holes, actually... Dec 11, 2010 at 20:58
  • and it's not only Swiss cheeses that have holes. Quality Gouda (hard to find these days even in the Netherlands) and many other Dutch cheeses have holes as well.
    – jwenting
    Apr 18, 2011 at 9:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.