IRA FLATOW: If you celebrated Valentine’s Day this week, you may have shared a delicious dinner with your loved one, including perhaps a variety of cheeses. Or maybe you went all out and did fondue. Oh, I love fondue.

Well, I’ve got some bad news for we Camembert and brie lovers. A lack of microbial diversity may be putting some of our beloved cheeses at risk of extinction. Oh, no.

Joining me to talk about this cheese crisis on the horizon is Benji Jones, senior environmental reporter at Vox, based in Brooklyn. Welcome back to Science Friday.

BENJI JONES: Hey, thanks for having me. And sorry it’s not under better terms.

IRA FLATOW: Well, sacré bleu, Benji. I mean, must we be prepared to bid adieu to our beloved French cheeses? How dire is the situation?

BENJI JONES: Yeah, I was very sad while writing this because I’m a fan of brie. But yeah, it’s not looking good for some varieties of cheese. So really, those bries and Camemberts, which are those fragrant, white soft cheeses, are at risk of extinction, according to a couple of French scientists that I spoke to at the French National Center for Scientific Research.

They’re concerned that the microbial diversity needed to make these cheeses is dwindling dramatically, and therefore, we may have trouble making them in the future.

IRA FLATOW: So remind us how these soft cheeses are made. It’s not the most appetizing process, is it?

BENJI JONES: Yeah. So I love learning about cheese and breads and other foods that are made using microbes because it’s this whole invisible world in the foods that we’re eating. And so, for cheese, it’s very similar.

So you take fresh milk. It’s cow’s milk in the case of brie and Camembert. And then the first step is to introduce usually a starter– so some bacteria and also rennet. And what that bacteria and rennet will do is curdle the milk. So it’ll go from this very smooth liquid to a gelatinous mixture. And then, that produces curds– hence, curdling.

And then, to go from there to cheese, you take the curds, essentially, smush them together, and then let them dry out. And different cheeses, whether they’re hard or soft, it often is just depending on how big those curds are that you start with, how much moisture there is, and how long you age it for.

So in the case of many cheeses, once you have those curds, the next step is to introduce yet another kind of microbe, which would be yeasts or molds– so different kinds of fungi. And in the case of Camembert and brie, they rely on a mold called Geotrichum candidum and also Penicillium camemberti.

And Penicillium camemberti is really the quintessential microbe, this mold that gives the Camembert and the bries that white fluffy texture and also a lot of their flavor. And that’s really where the problem lies, with this Penicillium mold.

IRA FLATOW: Well, what’s the challenge here? Why is it disappearing? Why can’t we just keep it going?

BENJI JONES: Yeah. So the short of it is that the genetic diversity of Penicillium camemberti, this mold that is essential for Camembert and for bries, is itself potentially going extinct. It’s lost all of its genetic diversity.

Really, if you look across the world at Camemberts and bries, any one that you find in the grocery store, the kind of mold used to make that cheese is identical– literally, genetically identical. So we’re not talking about different individuals of the same species, but, literally, it is the exact same individual that has just been cloned over and over again.

And the problem with repeated cloning is that it introduces errors into the genome– or at least it can. And in the case of this specific kind of mold, scientists have found that all that cloning has damaged its genome to the point where it’s more difficult to reproduce it, to clone it even at all.

And so the fear here is that it’s becoming really hard to clone this very specific kind of mold used for Camemberts and brie. And therefore, the supply chain of these cheeses is threatened.

So why do we just rely on this one particular strain? So what’s happened over many decades– at least for a century or so– is that cheese makers, cheese producers, have selected a very specific kind of cheese that they think looks good, smells good, is exactly what we think of when we think of Camembert– this fluffy white, flavorful cheese. And these cheese makers discovered that that fluffy white mold that we love is produced by this albino strain of a Penicillium mold. And that is the Penicillium camemberti. It’s an albino strain.

And so, over time, all these cheese makers were like, this is the very specific strain that produces the cheese that looks good, that tastes good, that smells good. So we’re going to only use this particular strain to make cheese. And over decades, all the other types of mold that were originally used to make these different cheeses disappeared out of disuse because they wanted this white specific cheese.

IRA FLATOW: Wow.

BENJI JONES: And so it’s this really intense selection force, this human-driven selection, of traits that we like in our cheese that have really lost all this genetic diversity. And now we’re learning that that comes with some important consequences.

IRA FLATOW: This is Science Friday, from WNYC Studios.

If you’re just joining us, I’m speaking with reporter Benji Jones about the cheese crisis on the horizon in France.

And so the cheese makers actually brought this on themselves.

BENJI JONES: That’s right. We see this with other foods as well. Consumers often like certain traits. They want all the cheeses that they see in the grocery store to look similar. They have expectations. And so farmers will select the specific– in this case– microbes that produce those phenotypes, those visible and physical traits in the cheeses.

IRA FLATOW: I’m thinking– you mentioned other foods– I’m thinking of the Cavendish banana, right?

BENJI JONES: Exactly. I mean, that’s to me the clearest parallel. Over years, we selected a specific kind of banana that tastes good, that ripens well, et cetera. And now, nearly all bananas that are exported are genetically similar or identical. They’re all this Cavendish variety.

And in the case of bananas– and this could be true for cheeses as well– when you have this lack of diversity, it’s not just a problem for reproduction, in the case of mold, but it can also be a problem when it comes to pathogens. So diseases that could wipe out one banana plant can also wipe out all the other banana plants if they’re genetically identical. So diversity is so crucial for resilience when it comes to food and when it comes to really biodiversity at large.

IRA FLATOW: Yeah, that’s wines, too, right? Grapes, the kinds of things we make for them.

BENJI JONES: Yes, exactly. Grapes, wheats, coffee even. I mean, this is especially relevant when we think about the ways in which the planet is changing. It’s getting hotter in some areas, drier. And what that means is that you need varieties of food that are more tolerant to things like drought. So making sure that you have that diverse group of plants to pull from, to adapt to some of these stressors that are getting worse, is essential.

And again, it’s just this tension with, over time, producers, they’re catering to consumers. And I think a big takeaway when I was doing this story, and as a cheese lover, is look, we have to just get more comfortable with diversity in our foods. It’s OK if the cheese is not perfectly white. It could be a little bit blue, for example, and it’s still OK.

IRA FLATOW: Yeah, this is a case of not form over function, but fashion over function.

BENJI JONES: Yeah, exactly. Exactly. We need to be a little bit more concerned with the things that make cheese resilient versus exactly what it looks like.

IRA FLATOW: Right. Well, is there no hope, then, for the future of French cheese? Or maybe we just have to accept not such beautiful looking cheese– or that we’ve been told is the way we should be eating it, right?

BENJI JONES: Yeah.

IRA FLATOW: Because if I hear what you’re saying, decades ago, they were very happy eating that kind of cheese, right?

BENJI JONES: Exactly. What I loved– I was talking to these researchers at that French Research Institute that came out with this finding– and they were saying, they looked at historical photos– these old paintings, actually, of cheeses– of cheese platters– you can kind of imagine what you might see in the Met or something, these really old paintings. And a lot of them had bries or Camemberts that had very different colors. So oranges and blues and grays and browns.

And so what the researchers think is that that was when the diversity of the molds used to make Camembert and brie were more diverse themselves. And that diversity produces different colors.

And the good news for us is that there is still lots of different molds out there that are diverse. So the closely related mold Penicillium biforme, which is closely related to Penicillium camemberti, naturally occurs in raw milk. And that will likely give those cheeses the same kinds of textures and tastes. It might make their color a little bit different, but that’s exactly the kind of mold that we can use. And those are much, much more easy to produce.

IRA FLATOW: Well, just like the cheese, Benji, we’ve run out of time. And it’s time to bid you a fondue farewell.

BENJI JONES: Yeah. And to your listeners, please say a prayer for Camembert, which is the best pun I could come up with.

[LAUGHTER]

IRA FLATOW: Benji Jones, senior environmental reporter at Vox, based in Brooklyn, New York.

BENJI JONES: Thank you so much.

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