To Brie or Not to Brie
Our favourite cheeses are under threat.
Most of us happily devour our cheese without much thought as to how it came to be; oblivious to the ecosystem that thrives in every slice. Over 100 microorganism species are easily found in any one cheese type. Each one plays an important role in creating the delicate taste and texture of our beloved cheeses.
Since coming to St Andrews, I have developed a deep appreciation for cheese. The cheese and wine nights held by my hall, as well as the late-night baked camemberts my friends and I have built into our routine, have sparked an admiration — or even a dependency — for soft cheeses.
Unfortunately, the cheese scene, not only in St Andrews but across the globe is about to change.
Our modern desire for uniformity when it comes to cheese production has put many of these microbe species in danger of extinction.
To make cheese, fresh milk is mixed with enzymes and fungi or bacteria. The large variation in flavours and textures of different cheeses comes down to the variety of microbes used. They produce enzymes which convert the sugars in the milk to lactic acid, beginning the fermentation process, as well as other digestive enzymes key to producing a cheese's distinctive taste.
A lack of microbial diversity in the cheese industry is putting certain French cheeses at risk. Camembert and brie are both produced using a fungus called Penicillium camemberti. This fungus is a fast-growing, albino strain developed from P. biforme, first used in cheese production a century ago. The issue with P. camemberti is that it reproduces asexually: all the individual fungi are clones of each other. This means a single harmful mutation can spread like wildfire throughout the population, as natural selection cannot intervene to ensure that deleterious mutations are wiped out.
Unfortunately, this path has happened for P. camemberti: the strain has picked up mutations that prevent the fungus from successfully producing spores, making it much harder to grow P. camemberti cultures.
Illustration: Magdalena Yiacoumi
Blue cheeses like gorgonzola and roquefort are also at risk due to the lack of genetic diversity in the P. roqueforti microorganism, used in blue cheese production. Similarly to P. camemberti, the domestication of the P. roqueforti strain through drastic artificial selection has decreased its fertility. It can no longer reproduce with other strains.
It has been proposed that genome editing technology could be used to counter the harmful mutations in our domesticated microbial populations and help them reproduce at a faster rate. However, Tatiana Giraud of the Centre National de la Recherche Scientifique in France clarifies that genetic engineering isn’t a solution: “Genome editing is another form of selection. What we need today is the diversity provided by sexual reproduction between individuals with different genomes.”
However, there is still hope for cheesemakers. Camemberts, bries and blue cheeses can still be made, they may just look and taste a little different.
Bleu de Termignon, a blue cheese produced on a small scale by a few farms in the French Alps, has the potential to save blue cheeses. Bleu de Termignon uses a previously unknown population of P. roqueforti which offers much-needed genetic diversity to gorgonzola and roquefort makers.
For camembert and brie, the P. biforme species of fungi offers hope. P. biforme is a very genetically and phenotypically diverse group of fungi and is able to reproduce sexually.
Whilst P. biforme produces a slightly bluer or greyer cheese, the strain is similar enough to be used in camembert and brie production. Cheese eaters will simply have to be open to a more diverse array of colours, tastes and smells in their cheeses.