Emmanuelle Ducros 8:57 a.m., March 27, 2024

Every morning after the 8:30 a.m. news, Emmanuelle Ducros reveals to listeners her “Journey into absurdity”, from Monday to Thursday.

A case of cheese and biodiversity this morning. Camembert and Roquefort could disappear from our cheese platters. They are threatened with extinction. And it may be the science of bacteria that will save them.

A fascinating story reported by the Journal du CNRS. Or when research changes our outlook on everyday life. The article tells how the domestication of the molds used to ferment these cheeses led to their slow degeneration and how, if we do nothing, we will no longer be able to use them.

Are the bacteria exhausted?

It's a bit like that. To make Roquefort, we use a species of mushroom called Penicilium roqueforti. Since humans learned to make blue cheese, they have selected only a few strains of this mold. Those which gave the most attractive cheese, with the best taste. The safest too, those which do not produce toxic substances. And then, those that grew quickly on the cheese so as not to leave room for other unwanted bacteria.

We sort of raised mushrooms.

Yes, but not as we do with animals, by crossing bloodlines to bring in new blood. We did not take care of the biodiversity of molds – and for good reason, we knew almost nothing about it. 

Mushrooms have most often been cloned by the industry, to obtain a stable result. Big drawback: they all end up being the same. The strain degenerates. She becomes sterile. And it is our Roquefort which is threatened.

Same thing for Camembert?

Yes, worse. We are talking about another mold, Penicilium camemberti. All Camembert-type cheeses are produced from a single strain everywhere on Earth. This strain is a white mutant selected in 1898. It gradually replaced other strains, which produced green, orange or blue-gray pie charts. They were still found in France in the 1950s. The strain is dying. Manufacturers are having trouble getting enough.

It's frightening ! Can we save our cheeses?

This is where science comes in and it's fantastic. CNRS researchers recently discovered a new strain of penicilium roqueforti, in an alpine blue, which is called Termignon blue. It could provide the genetic renewal that historic strains need. It's a little more difficult for Camembert. The researchers set out in search of wild penicilium camemberti, or similar molds to cross them. It's possible, because we know how to sequence the mold genome!

Will this have consequences on the cheeses?

Yes ! Perhaps less standardization, since the fresh molds will bring new taste characteristics that we don't really know yet. Good news ! This will bring more microbiodiversity and more new tastes to our plates.