Sometimes there is the wildest speculation as to how the holes in our cheese come about. But one thing is certain:
It's not the mice that eat the holes in the cheese, even if the children imagine it that way in their imagination. The dairy employees with their cheese drills are not responsible either. With the drills they only check the cheese after it has been made. The fact is that bacteria do this job.
The secret lies in the cheese maturation.
Cheese is made from milk. Milk consists mainly of fat, protein and lactose. At the beginning of cheese production, specially cultured bacteria called lactic acid bacteria are added to the milk. The bacteria attach themselves to the milk components and convert them. They breathe out carbon dioxide (carbon dioxide). Since the gas cannot escape through the dough and the rind, it accumulates in cavities of different sizes in the cheese mixture. These are the holes in the cheese.
How big the holes are depends on the type and amount of bacteria and the firmness of the cheese mixture. For example, the Emmentaler is stored in a fermentation cellar at 23°C for a few weeks - this is how the large, typical holes are created.
Swiss researchers were able to solve the mystery of exactly which mechanism is responsible for the accumulation and distribution of holes in Emmental cheese. They found that microparticles from plants - presumably from hay - are present throughout the milk. The carbon dioxide that is produced during ripening attaches to these small particles.
Through experiments with filtered, unfiltered and milk mixed with hay powder, the scientists were able to show that the amount of hay particles is crucial for the number and size of the holes in the finished Emmental.
Now that was exciting, right?!
If the milk in the dairies is too clean because there is no wood dust left, then there are only smaller and fewer holes!