Ever wonder why Swiss cheese has holes? Swiss cheese hole mystery finally solved

Scientists have finally solved a mystery that has baffled them for a century – why does Swiss cheese have holes?

Contrary to what cartoons have suggested over the years, the holes are not made by mice eating their way through the cheese.

Swiss laboratory says they are created by flecks of hay. These “microscopically small hay particles” get into the milk and create holes as the liquid matures into cheese.

Agroscope, a government agricultural institute, said “microscopically small hay particles” would fall in to buckets collecting milk, and develop into bigger holes as the cheese matures.

The process affects only some Swiss cheeses, such as Emmental and Appenzell.

The discovery also solves another riddle – why the famous holes in cheeses like Emmentaler or Appenzeller have been getting smaller or disappearing completely over the last 15 years.

Scientists reached their conclusions after adding small amounts of hay dust to milk and making it into cheese over 130 days. The research has not been peer reviewed.