This is a transcript of the Gastropod episode Yes, You Really Can Make Food From Thin Air—And We Tried It, first released on November 4, 2025. It is provided as a courtesy and may contain errors.

NICOLA TWILLEY: Here we go, here’s my first food from the air ever.

CYNTHIA GRABER: [LAUGHING] It feels so science fiction. I mean, the fact that it actually was created literally from air…?

TWILLEY: I know.

GRABER: I can’t even imagine. So I’m going to get out a… knife here.

TWILLEY: I am pretty excited. So I need a knife and a plate, and I have some bread.

GRABER: Yes, you heard that right, Nicky and I were about to taste food that was literally created out of thin air!

TWILLEY: And it wasn’t imaginary. It was real! Real spreadable, meltable, edible butter made from air.

GRABER: Right now you’re probably all wondering: what in the world are you talking about? And we are going to answer that question this episode of Gastropod! You are indeed listening to Gastropod, we are not science fiction. We’re the podcast that looks at food through the lens of science and history, I’m Cynthia Graber.

TWILLEY: And I am Nicola Twilley, and this episode: can we really bypass plants and animals and just get all our nourishment from the same stuff we breathe? And why on Earth would we want to?

GRABER: This episode is supported in part by the Alfred P Sloan Foundation for the public understanding of science, technology, and economics. Gastropod is part of the Vox Media Podcast Network, in partnership with Eater.

[BREAK]

TWILLEY: OK, before we get to the future, we need to make a brief stop in the past, where the future was being invented, to meet a Frenchman named Marcellin.

BILL GOURGEY: Marcellin Berthelot was a renowned chemist from the 19th century. His claim to fame really was synthetic chemistry. Synthetic chemistry being combining elements to make new compounds, versus analytical chemistry, which is taking apart compounds to get to their elements.

GRABER: Bill Gourgey is a science writer, and he told us that Marcellin’s research wasn’t about creating food from air exactly. But it set the stage for that because he had the idea that we didn’t need plants to create food.

TWILLEY: This was a really radical idea. Most of everything we eat comes from plants originally.

KATHLEEN ALEXANDER: So if you think about every calorie you’ve ever eaten, it really all starts with, kind of photons coming from the sun. And that form of energy getting transformed into food molecules through agriculture.

GRABER: Kathleen Alexander is co-founder and CEO of a food from air company called Savor.

ALEXANDER: And so, to kind of really have humans thinking about like, do we need this agricultural paradigm to make food? That didn’t really get started until we, until we started understanding, you know, how to think about molecules.

TWILLEY: Which was in the 1800s, when chemistry as a science emerged. And one of the first things these new chemists did was figure out what food was made of.

GOURGEY: So food really is—you know, we think of like carbohydrates and proteins and lipids, right? Fats. You could throw in vitamins and minerals. And those are probably like the five sort of basic categories, to simplify. But. I mean, carbohydrates are what the name says. They’re carbon, hydrogen, and oxygen, and that’s it. From carbon, hydrogen, and oxygen we get sugars, you know, like glucose and fructose and sucrose, and we get starches which are sort of long chains of those sugars.

GRABER: The same is true for protein—if you just add one extra element, nitrogen.

GOURGEY: It’s made of these amino acids that are carbon, hydrogen, oxygen, and nitrogen. And that’s it. And lipids or fats—those are, same thing as carbohydrates: carbon, hydrogen and oxygen. The chemistry’s a bit different, so they’re insoluble in water, but that’s it.

GRABER: I’m going to repeat this, because it’s kind of mind blowing: All food at its core, from fish to bread to oranges, the so-called macronutrients that are the basis of these foods—fats, proteins, carbs, they’re all made up of carbon, hydrogen, oxygen, and nitrogen. Like Bill says, that is literally it.

TWILLEY: But at the time, in the 1800s, a lot of leading chemists thought there was something else in organic living matter—some kind of vital spark or force, something that we humans couldn’t make.

GRABER: Marcellin Berthelot didn’t agree with that point of view. He argued that if we combined the molecules from nonliving stuff in the right ratio, well, then we could make something that was chemically identical to organic living matter.

GOURGEY: And he was a real advocate for synthetic chemistry, and believed that, you know, synthetic chemistry was going to replace the entire food chain.

GRABER: Marcellin created all sorts of useful things in the lab from chemicals, not from air. But he even was able to create fat in his lab. The fat in our diets comes from living things—it comes from plants, or from animals. This didn’t. That said, it wasn’t food, not the way he’d imagined it, but he’d done what a lot of people thought was impossible.

GOURGEY: And so he was really sanguine after having so much success on the notion that, you know, it would just be a matter of time, and not much time, before all foods were manufactured from these basic elements. Of course, there were a ton of skeptics, at, at the time. But there really was this rising tide of optimism about the future of chemistry, and where it was all going. And it, and it really started right around that time.

GRABER: Marcellin died in the early 1900s, obviously his vision hadn’t been implemented by that time. And his son Daniel was also a scientist.

GOURGEY: He was determined to realize his father’s dream of creating food directly from chemicals.

TWILLEY: But Daniel figured, you know, plants already know how to do this, maybe I can steal their secrets and then cut them out of the process.

GRABER: Nobody understood photosynthesis at the time. Today we know that this is a complicated process that plants have evolved, but Daniel thought it was super straightforward. He thought plants just absorbed sunlight and gasses and bam, they created food.

GOURGEY: I mean, that was really it. And so he had this very sort of simplistic and almost romantic vision of what it was that happened in the photosynthetic process.

TWILLEY: Daniel set up his research laboratory in a park just southwest of Paris. It was called the Garden of Wonders. He had lots of plants growing in glass containers and pipes filled with different gases.

GOURGEY: But probably the, the coolest thing that he had was these glass tanks, inside the buildings, where he set up ultraviolet lights.

GRABER: The tanks didn’t have any plants in them, and they didn’t look like much was going on, they just looked empty. But, he was pumping oxygen, nitrogen, hydrogen, and carbon dioxide into the glass tanks, then shining ultraviolet lights on them to mimic the sun—

GOURGEY: And waiting for the magic to happen. [LAUGH] And his, his vision of, of that magic and what that magic would look like—he sort of predicted that the starches would spontaneously develop. In the air. And fall to the tank bottom, like snow. And you know, that it would be shoveled up and those would be the starches that could be turned into, into food.

TWILLEY: Super cool. And it totally didn’t work. Because Daniel didn’t realize that plants have a whole set of chemical reactions going on inside their leaves that turn the energy from light into chemical energy. And then use that energy to break apart carbon dioxide and water into their elements and then combine them with other things like minerals to build something we can eat.

GRABER: Daniel might have gotten this wrong, but he wasn’t a total loss as a scientist. He did synthesize a compound called formamide that was later used to create important drugs. Formamide is a precursor for amino acids, which are the building blocks of protein, and it’s also a precursor for sugars. And, if you heat formamide, it can break down into the precursors for fatty acids.

TWILLEY: Daniel didn’t actually get to amino acids or sugars, at least as far we know. But still, that’s not nothing, though it’s still a long way and a bunch of chemical reactions away from anything even resembling the building blocks of food. And soon after this milestone, Daniel died. So that was that.

GRABER: But the science of using chemistry to build molecules people needed kept going. In the 1930s, German scientists were able to create margarine using chemicals from coal. Of course coal is kind of decomposed plant material, but turning coal into chemicals that you can combine into fat is very different from pressing olives for their oil, or having a cow eat grass and then turn that into milk that we use to make butter!

TWILLEY: Also in the ‘30s and also in Germany, scientists figured out how to make an amino acid by combining industrially produced chemicals. This amino acid was used in animal feed, but it wasn’t exactly a steak or a bean or anything you could recognize and eat and fulfill your body’s need for protein.

GRABER: This was all happening when Germany was gearing up for war and expecting food shortages. And then there were all sorts of shortages during the war. But afterwards, something dramatic changed, and that’s the expansion of industrial agriculture.

TWILLEY: We’ve talked about this before on the show, but all that production of weaponry and heavy machinery and explosives? Some of it got repurposed to make fertilizer and pesticides and tractors. Meanwhile, researchers focused on boosting crop yields and efficiency, and we had what is known as the Green Revolution.

ALEXANDER: One of the things that really took off right around the time that these types of processes were being developed, was agricultural seed oil production. It tends to be kind of lower in, in capital costs, right? We don’t often times pay any cost associated with clearing land or, or removing forests. And so there’s kind of less of a barrier to scaling up for example, vegetable oil production globally.

GRABER: What this all meant was that you didn’t need synthetic lipids, like the ones the Germans had been developing. It was cheaper and easier to just go out and rip up rainforests and plant palm and soy fields.

TWILLEY: Yay capitalism. But while we were busy building this brave new world, we were also dreaming of traveling to other worlds.

MONSI ROMAN: During the Apollo missions, during the early, early missions that were just sometimes hours or days, food was taken with them. You know, and in the very early stages it was like pasty food. So it was not even good tasting food. It was more about the nutrition.

GRABER: Monsi Roman is a former administrator at NASA.

ROMAN: Then as we started evolving towards the era where we were flying astronauts for about two weeks, we started sending food that was in- in packages, right? But it was more like real food, but dehydrated. You know, you will take it in your mission and put the water in.

GRABER: While NASA was figuring out how to feed those early astronauts with delicious treats like freeze-dried ice cream, they also started thinking about what space travelers might need on a longer journey, like maybe to Mars.

TWILLEY: It might sound appealing to eat astronaut ice cream for months on end—or maybe not. But either way, it’s not an option because you simply can’t carry enough of it in your space rocket. Folks at NASA quickly realized that if humans are ever going to settle in outer space we would need to figure out how to make food where we’re going, rather than take it with us. So researchers started wondering whether they could use exhaled carbon dioxide and feed that to a friendly microbe, and have that microbe reproduce and ultimately sacrifice itself to yield edible, protein-rich cells for dinner.

GRABER: This was kind of a thought experiment at the time based on some research NASA had been doing with bacteria, but it didn’t really go anywhere. Because the technologies needed for the whole process just weren’t there yet. But a lot has changed in the past sixty years or so.

COLLIN TIMM: I think a big turning point was the CO2 capture technologies. If we didn’t have that, it, it would be almost unthinkable to be able to do this.

TWILLEY: Collin Timm is a scientist at Johns Hopkins Applied Physics Laboratory. And his point is that today, the big breakthrough is that we have at least feasible ways of capturing carbon dioxide from the air.

TIMM: We are using technologies developed in the energy industry. Where they’re trying to recapture CO2, reduce pollution. So that companies can remain compliant and not pollute the world. We want to take those same technologies and, and use it to produce things like food.

GRABER: Collin’s lab is working with the government, with DARPA—that’s the Defense Advance Research Projects Agency. DARPA wants to be able to make food from air for soldiers traveling into remote regions.

TIMM: They’ve got all their, you know, trucks moving with them, their supplies. But one thing that they are dependent upon is having food brought in to them, fresh food, at some regular basis. That slows them down. That means they can’t be as agile in the field. They need technologies that allow them to disconnect from that supply chain of trucks coming in to their field forward position.

TWILLEY: Figuring out how to feed the military in the field has often led to innovations that then end up feeding the rest of us—that’s how canning was invented.

GRABER: NASA may have let this slide for a few decades, but they’re back on the food from air science beat now too.

ROMAN: And, and it is kind of something needed anyway. You know, we need to process the CO2 that the crew is breathing out during a mission, inside a can—basically, it’s a can, a closed can. So we have to take that CO2 and do something with it.

GRABER: So why not try to use it for food?

TWILLEY: If you don’t do anything with it, carbon dioxide levels would build up in a space habitat and become a problem. But guess where else that’s happening? Yes, right here on our own precious planet Earth. Where our food system has many other problems associated with it too.

JUHA-PEKKA PITKÄNEN: So that CO2 levels are really increasing and the, the kind of agricultural land area is diminishing and we are cutting more rainforests to, to get more fields.

GRABER: Juha-Pekka Pitkänen is chief scientific officer and co-founder of Solar Foods. His company and Kathleen’s company were both founded out of a desire to help improve the situation for everyone right here on earth.

ALEXANDER: My co-founder at one point was like, up in an airplane, looking out the window, and just kind of marveling at the extent to which we have subdivided like, 50 percent—it turns out—of the habitable land on this planet to produce food. And I think it really begs the question of: is it necessary for humans to consume planet Earth, in order to feed ourselves? And the possibility of, kind of, being able to feed ourselves with much fewer resources is actually very compelling, I would say.

TWILLEY: So whether you’re in space, on the battlefield, or just a regular human, the motivation to make food from air is definitely there. But you need more than motivation to actually make it work. Monsi said that when she was launching this project, she talked to a NASA expert who said turning carbon dioxide from the air into useful and maybe even edible stuff was one of the hardest challenges he could even imagine.

ROMAN: And we were like. That doesn’t sound that difficult. And he goes, no, no, no. Trust us. You know, this is not going to be easy.

GRABER: Collin never thought it was going to be a snap.

TIMM: It is a very hard problem. And it was a convergence of a lot of technologies and a lot of experts working on their part of the problem. We had to bring in people who could build and understand the CO2 capture system. Then we had to bring in the engineers who understood how to turn that CO2 into the small molecule products that microbes could eat. And then we had to bring in the experts that understood how to engineer microbes, such that when they ate those small molecule products, it would produce glucose.

TWILLEY: This was Collin’s big plan to bypass photosynthesis. Grab the gasses you need from the air, press-gang a friendly microbe into service, and bingo: glucose is served. But man cannot live on glucose alone, so what happens next to make that sweet microbial sugar into actual food? That’s coming up, after the break.

[BREAK]

GRABER: Collin said that his research team is using microbes to make food.

TWILLEY: Which means you can all take a drink, if you haven’t already.

GRABER: And this one of the two major methods scientists can use for turning air into something edible. They can grab gasses and find the right microbes that can thrive off those gasses to produce something edible for us.

TWILLEY: Like the NASA vision from the ‘60s. Or, method number two, they can go back to Marcellin Berthelot’s big idea, and just grab gasses, extract the elements they need, and make food using pure chemistry—no life forms required.

GRABER: Scientists today are tackling this challenge using both of these approaches. Collin and Juha-Pekka are using the microbe approach—and while we said that carbon capture technology was critical to making this feasible, so is genetic sequencing technology. That’s how both teams can quickly search through microbes, discard the ones that won’t work, and find just the right microbes for the job. Collin’s also been using genetic engineering to help him on this microbial adventure, and that’s something where we’ve made a lot of progress in the past decades.

TWILLEY: Collin’s brief from DARPA was very specific: they wanted something that would work at the front lines. In other words, the whole machinery to grab the gases and turn them into microbe food and then turn that into human food. It had to be small.

TIMM: Yeah, so we envision a system that could mount on like a truck. It sits on the back of a pickup truck. It’s got an air processing system that pulls in hundreds of meters cubed of air per day. That scrubs out all of the carbon dioxide and captures that carbon dioxide.

GRABER: And for that technology, while usually you’d think of starting in a lab, making something small as a trial, and then scaling it up, Collin had to ask researchers who’ve worked on carbon capture systems for power plants to do the exact opposite for him.

TIMM: And we asked them, Hey, we know that you’re used to building systems for plants. Can you make us something that would fit on the back of a truck, and feed into a bioreactor? They developed novel catalysts, novel reactions, such that they could do that for us.

TWILLEY: Which is great, so now Collin has carbon from the carbon dioxide in air. But most microbes can’t eat just plain carbon. You have to use chemical reactions to put those carbon molecules together into stuff they can eat.

TIMM: So you can get things like formate, acetate, probenate. Molecules that by themselves we, as humans, can’t consume. We need to upgrade those molecules into something more complex. And it turns out that microbes are a really good way to do that.

GRABER: The microbes feed on things like acetate and create things like glucose. But these aren’t food-safe microbes, we can’t eat them. So Collin and his colleagues have selected a whole extra team of microbes to eat what the first microbes have excreted.

TWILLEY: This second team of microbes, they’re food grade, and they’re engineered to contribute the right ratios of carbohydrates, proteins, and fats. But still, at this point, Collin’s microbe-feast is nutrient rich, but it’s not exactly food. His ultimate goal was to make a yogurt-like substance. So he recruited a couple more microbes.

TIMM: So we have selected a different set of microbes that produce gelling agents. Xantham gum is something you can find in your grocery store today. That’s a microbial product that we were able to produce as well. And then lastly, in order to have something that really resembles a yogurt, it’s got to have the right flavor profile. So we engineered microbes that could produce molecules like vanillin, that give them that vanilla-like flavor. Ultimately, that allows us to produce a yogurt material that has a vanilla flavor.

GRABER: And, drumroll—this project has actually worked! They’ve made about half of like a container of single-serve yoghurt!

TIMM: Yes. We made about a hundred grams of the product already on the project. And we use that as a kind of a show and tell for, here’s what food from air looks like.

TWILLEY: DARPA rules say that this yogurt material is not actually approved for human consumption yet, so Collin couldn’t tell us anything about the flavor. But he was pretty excited about the texture.

TIMM: Oh, absolutely. You could scoop it up with your finger and it had the little flip of texturized material that you’re looking for in, in something that you would call a yogurt, right?

GRABER: This is genuinely impressive, and everything that went into that yogurt, other than the microbes, came from the air. But this particular air food is not ready for the battlefield just yet.

TIMM: So our project was all about demonstrating the prototype. It took us about six months to get that hundred grams of product from those air materials.

TWILLEY: Obviously that would speed up once they got beyond the prototype and into regular production. But Collin estimates making yogurt material from air on the battlefield is at least a decade away. Of course, he’s taking a very purist approach—all the raw ingredients that the microbes use have to come directly from the air, and the result has to be edible without any further processing.

GRABER: Juha-Pekka has taken a different approach, and his has worked, too. In fact, Solar Foods already has a commercial facility that’s using microbes to make food from gas in the atmosphere, it was the first of its kind. But it’s a much more pared down type of food.

PITKÄNEN: So essentially, the main raw materials are electricity and CO2. And from these raw materials we make protein-rich powder as a food ingredient.

TWILLEY: For this slimmed down, scaled up process, Juha-Pekka only uses one microbe.

PITKÄNEN: We call it SoFi. So it’s SO F1.

GRABER: Like Solar Food 1. Juha-Pekka’s idea is that just the microbe itself is the final product, and it’s an ingredient that can be used in food. It’s not like what Collin wants to create, which is a mix of microbes and microbe excretions that are blended together to create a food—a yoghurt—that you can just grab a spoon and take a bite. It doesn’t need any further processing.

TWILLEY: And because Juha-Pekka wanted to use just one microbe to eat air and then get eaten itself as part of a food, that microbe had to be pretty special. He told us that to be sure that Sofi wouldn’t be harmful to humans, she had to be the type of microbe that doesn’t use chemicals to harm other microbes around her, because if she did, that could also make her toxic to us.

PITKÄNEN: So basically for us, we kind of wanted to find a—or kind of needed to find a pacifist microorganism.

TWILLEY: When Juha-Pekka and his co-founder started Solar Foods in 2017, they went out looking for this special pacifist microbe. And they found SoFi in the sediment of a Finnish bog.

GRABER: But then they need to get SoFi’s food. She needed hydrogen, oxygen, and carbon.

PITKÄNEN: So we use electricity to split water into hydrogen and oxygen. So that’s the way we get hydrogen and oxygen. And then CO2—so we have in our demonstration factory we have direct air capture. So it captures air from CO2 from air.

TWILLEY: Being completely honest, not all the carbon that SoFi eats comes from the air, because capturing carbon from the air makes that carbon very expensive. Because while the technology exists, it is still very much in the prototype phase right now.

PITKÄNEN: I mean, it is still the most expensive CO2, to capture it from air. So we are doing that for demonstration. To test how the technology works.

TWILLEY: Juha-Pekka told us that right now, most of SoFi’s carbon intake comes from the carbon dioxide released when you make lime, a common agricultural product that’s used to boost soil productivity. This would normally be released into the air from the factory as pollution, but instead Solar Foods captures it for SoFi’s dinner.

GRABER: And it also turns out that SoFi needs more than just carbon, hydrogen, and oxygen to survive. She also needs trace elements: zinc, cobalt, and potassium. As we said, Juha-Pekka isn’t a purist, so he buys the minerals from a supplier and adds them to the mix too.

TWILLEY: And then, once SoFi is fed and happy and has grown and multiplied into many many SoFis, she’s nearly ready to be eaten. But first she has to die.

PITKÄNEN: So we have a pasteurization step, and—yeah, sorry to say, so then we kill the organism.

GRABER: At that point, they separate out all the microbes from the solution they’ve been living in. They dry the whole mess out, and then you have this powder, it’s an edible powder made entirely of dead microbes.

PITKÄNEN: So it happens to be vibrant yellow color. So this yellow color comes from carotenoids.

TWILLEY: As well as the carotenoids, the powder is about three quarters protein, with just a little fiber and fats.

GRABER: It might sound futuristic to create an edible protein-rich microbe-based powder, but actually this type of food has a long history. We told you in our Mexico City episode that the Aztecs used to scoop our bright green algae called spirulina and dry it for food, this also is super high-protein and it’s also dried dead microbes. Same concept.

TWILLEY: And just like dry plain spirulina powder, the taste of SoFi just by itself is not much to write home about.

PITKÄNEN: So as a dry powder, well, it is very dry powder. It has a bit of a, like a… corn puff taste. I mean, there’s a, maybe a little bit of carrot taste. And then maybe a bit umamic.

GRABER: Slightly like a corn puff, slightly carrot-y and lightly umami sounds okay, but it’s not so appetizing just on its own. So what the Solar chef does in their test kitchen is mix the powder into things.

PITKÄNEN: So for me, nice examples have been ice cream. And then also in pasta. Basically in vegan ice cream, it gives kind of firmness to the texture. And then in pasta, also, in fresh pasta. It then replaces egg yolk. So again, it gives kind of, more texture, it’s more moldable.

TWILLEY: Because it’s a new kind of food, Solar has had to get approval from food regulatory agencies in all the different countries it wants to sell in, which means having to jump through a lot of hoops to prove SoFi is safe to eat. Juha-Pekka told us that was the hardest part of the whole thing. But they’ve succeeded, so now SoFi is on its way to a supermarket shelf near you.

PITKÄNEN: So in Singapore we have had some sales of ice cream. So this have been by Japanese company, Ajinomoto. And in US, we are in process with our partners to bring products to the market.

GRABER: In the US, they’re focusing on so-called health and nutrition products, like protein powders, protein bars, protein mix-ins, those types of things. These kinds of products are already on the market—right now they use animal or plant protein—and there’s already a market for them. So this is a good way to get a foothold and some income, which could help them expand.

TWILLEY: It’s kind of amazing: this was NASA’s vision in the 1960s, and here it is finally for sale—at least in Singapore. We figured Juha-Pekka must be feeling super proud and excited.

PITKÄNEN: Feelings? I’m a Finnish man. I don’t have feelings. Or I don’t express feelings, let’s say.

GRABER: That said, he did find a way to kind of cautiously express a slightly positive emotion.

PITKÄNEN: Yeah, so, nice, but still acknowledging that there is still so much work to be done. So that kind of, from the initial discovery, it is maybe, I don’t know, 10, 20 percent. So that it is, it just gets steeper and steeper, the hill.

TWILLEY: Ain’t that true, buddy. About basically everything. But meanwhile, although we at Gastropod love microbes.

GRABER: Yes, okay, you can have another drink—

TWILLEY: We should raise a glass to Juha-Pekka and Collin’s successes for sure. But, it turns out you don’t actually need a microbe to make food from the air. That story, coming up after the break.

[BREAK]

GRABER: As we said, if you’re thinking about how to make food from air, there are two basic ways to go about it:

ALEXANDER: Do you want to use the machinery of organic chemistry or do you want to use the machinery of biology?

TWILLEY: Chemistry is how the Berthelots, father and son, thought we should make food from air, and chemistry is how the very first synthetic food substances were made: margarine from coal, and a couple of amino acids from various industrial chemicals.

GRABER: We told you about those amino acids, they’re the building blocks of protein, and the protein we eat contains 20 of them. We need lots of different ones, so just eating an amino acid isn’t complete, not like eating protein.

TWILLEY: But—and here’s where it gets intriguing—you can’t actually build most of those amino acids using pure chemistry. Because of whether they’re left handed or right handed. This is a weird thing in chemistry where it turns out that many molecules, their structure isn’t symmetrical. That means they can have what’s called a left handed orientation or they can have a right handed orientation, and that difference affects how they behave and even whether we can digest them.

GRABER: Some molecules don’t have this problem. Like there’s one amino acid called glycine where there is no left and right handed form, and so it’s easy to synthesize using just chemistry. And we do that in industry. We do it easily and we make boatloads of it.

TWILLEY: But like we said, glycine isn’t dinner on its own. It’s a single amino acid, not protein, and it’s certainly not food. Whereas a microbe can make digestible protein and sugar and whatever else, and it naturally only makes the version of a molecule we want. So: why would anyone want to use just chemistry?

GRABER: Well, it turns out there are benefits. When you use biology—when you use microbes —they need certain conditions to survive and thrive. They need the right temperature, the right pressure, and most importantly these microbes need a medium to live in, usually a water-based one. And it actually takes a lot of energy to smush all the gasses into water—that is, to dissolve them. That’s what Collin and Juha-Pekka have to do to give their microbes gas slash food.

TWILLEY: You don’t have to bother with that if you’re just making food from chemical reactions, so it can be faster, cheaper, and more energy efficient.

GRABER: But then how do you get around the left and right version problem that a lot of molecules have? Well, Monsi told us that one company that NASA worked with figured out an entirely new solution.

ROMAN: So on this one in particular, this company, Air Company actually developed a way of using CO2 to make a molecule, a sugar, in this case.

TWILLEY: Like we said, astronauts in space are already breathing out a lot of CO2—it’s a waste product. And NASA wanted to see whether anyone could come up with a way to turn this waste product into something useful.

GRABER: Air Company wanted to make sugar, they wanted to make glucose. They first turned carbon dioxide and hydrogen into methanol. Methanol isn’t sugar, so they needed a few more reactions, it went from methanol to formaldehyde—that’s not edible. Then they made sugars that are toxic, and then they could turn those into glucose. And this was all chemistry.

TWILLEY: All the glucose in nature is right handed. If you synthesize left handed glucose in the lab, it tastes sweet but no living organism can digest it. Plus, apparently it has a laxative effect. The chemical reaction Air Company was using would normally produce a mix of left and right-handed glucose molecules, but all those left-handed ones are not good to eat. So their big breakthrough was to develop a special enzyme to add to that final chemical reaction that made it so only the right handed glucose was produced.

GRABER: Amazing! But glucose wasn’t going to be enough to feed astronauts on a long-haul flight, so Air Company’s original idea was to take that glucose and feed it to, yes, microbes.

ROMAN: Yeast in this case, which, you know, it’s pretty easy to do. And then from there, make food. Make the components of a powder that can be nutritious and can potentially have some taste. That can be part of something that might look like a protein shake, perhaps.

TWILLEY: There’s still a lot of steps between the chemical reactions and the protein shake. And as Monsi said, a microbe would still be involved somewhere along the line. But Air Company did successfully produce glucose from the air without any microbe helpers.

GRABER: NASA cares about glucose for space missions, but sugar is pretty cheap today here on Planet Earth. So now what Air Company is doing is they’ve tweaked their chemistry to take gas from the air and make something to help us fly through air.

ROMAN: Right now they’re doing, they’re using a process very similar to do fuels for airplanes and perhaps even on Mars, you know, rockets and such.

GRABER: So food is kind of on the backburner for Air Company at the moment. But it turns out there’s another edible product whose molecules don’t have a left and right problem, which makes them perfect for creating using chemistry.

ALEXANDER: With fats, there are actually many fats, including the ones we make at Savor, that don’t have any symmetry at all.

TWILLEY: Kathleen’s company, Savor, uses the same raw ingredients as everyone else: carbon, hydrogen, and oxygen. They get the hydrogen and oxygen from water. In the future, they could get carbon from carbon dioxide in the air. But for right now, they get it directly from emissions sources like cement plants and power plants. Then they do a couple of chemical reactions to transform those raw ingredients into paraffin wax.

ALEXANDER: That’s a very energy-dense substance. It’s also very useful in its own right. With the exception that it is not fuel for your body.

GRABER: Converting it into fuel for our bodies takes another round of chemical processes, they basically add oxygen to the wax and that turns it into a fatty acid. And fatty acids are the building blocks of fats that we eat. At that point they have to add some glycerol, which they buy, and that binds those fatty acids together into an edible fat.

ALEXANDER: And so that’s kind of where we start, is this very pure fat without any water in it. And then to get it to behave like a butter, you have to emulsify it into this, like, very creamy, buttery thing.

TWILLEY: Notice how Kathleen calls it a creamy, buttery thing. That’s because it’s not actually butter.

ALEXANDER: The name that you’ll see is MLCT oil. Medium long chain triglycerides. And so what that is indicating is that there’s this mixture of medium chain fatty acids and long chain fatty acids that are present in our butter. And those then are going to get metabolized in your body just exactly like those fatty acids already get metabolized in the foods that you eat.

GRABER: MLCT oil is just a type of oil, you can even buy this in supplement stores today. But when Savor thought about what to do with their MLCT oil, how to create a food that people can cook with, they decided to create a stick of butter.

ALEXANDER: We were very intentional in deciding to make butter first to as the kind of fat we wanted to, to share externally. Because it’s one that people already have some expectations around. They already kind of know what to think about butter.

TWILLEY: They do indeed. I think about it with great affection. Butter holds a special place in my heart for its sheer delightful butteriness. So how do you make MLCT oil compete with that?

ALEXANDER: So the kind of neat fat, as we like to call it, has a very neutral flavor. There’s kind of like hints of creaminess, but compared to a butter, it’s actually very light in flavor.

GRABER: So they add some flavorings to the final product to make it a little more butter-like. To get those grassy notes, for instance, they add a little rosemary and thyme oil.

TWILLEY: And we straight up spooned this air butter into our mouths.

GRABER: It’s actually like-—it’s creamy. It’s a little bit salty. It’s a little grassy.

TWILLEY: Yeah, I get that rosemary. I mean, it’s good.

GRABER: We did have regular butter-butter out to compare it to, of course.

TWILLEY: Hmm. [LAUGHING] I do actually love butter.

GRABER: The butter definitely has that like a dairy thing going on.

TWILLEY: The butter is A, better and B, definitely it’s got a more… I would say, cheesy note almost. Which I guess is your dairy. It’s like salty, savory. And it’s a tiny bit of a different melt, too. Like the butter is creamier and the air butter is a little mousse-ier, if that makes sense.

GRABER: We spread the air butter on bread to test that out, and it spread well, too.

TWILLEY: I am not going to lie, I love butter, but the air butter is quite good.

GRABER: I have tasted a lot of vegan butters, and they’re okay. This as a non-dairy, but still sort of dairy butter? It’s actually quite delicious.

TWILLEY: Kathleen told us that Savor started out with butter but they’re not limited to butter. They can tweak the fatty acid structure to create fats with all sorts of different properties.

ALEXANDER: We, for example, you know, make liquid oils, we make fry oils, we made, you know, beef tallow equivalents and lard equivalents. And we could differentiate that from a beef tallow that’s like a little bit earlier melting, like a corn fed beef tallow. Or like a grass-fed beef tallow’s like a little waxier or a little harder.

GRABER: And they’re partnering with chefs to test out these different fats. They sent us a box of four bonbons that were totally vegan—the ganache inside is usually made with cream, but the dairy fat in these was Savor’s air-made variety.

GRABER: Amazing mouth feel. Totally delicious. Beautiful piece of chocolate. I don’t know. I don’t have anything to complain about. [LAUGH] It’s really good.

TWILLEY: It’s a little chocolate with a ganache center, that tastes exactly like a chocolate with a ganache center.

GRABER: Yeah. I mean, the texture is like, perfect.

TWILLEY: Mm! Ten out of ten, no notes on that.

GRABER: As we said, Savor can make a variety of fats, but right now they can only make the saturated kind, these are like animal fats and palm oil and coconut oil. That’s because these fats don’t have the left and right-handed issue.

ALEXANDER: You absolutely can make unsaturated fatty acids. You can make Omega-3 fatty acids. Those actually start getting you into that thing we talked about at the beginning.

GRABER: You know, how some molecules have left- and right-handed versions. That’s an issue with the omega-3 fatty acids.

TWILLEY: At which point you need something like Air Company’s special enzyme, to make sure you only get the version you want. So that is more complicated, and definitely something for down the line.

GRABER: But even so, just making saturated fat, that gives Savor both a huge market and an opportunity to have a really important environmental impact.

ALEXANDER: So our commercial and scale-up focus has really been on, you see us talking the most about animal fats and tropical oils. Because that’s where the agricultural footprint is the largest for fats and oils. And so our goal is about: how do we shrink the footprint that we produce food for humans on? And so, and land being the literal version of that, but then also emissions and water and biodiversity loss. And so palm oil fits into that equation. Animal fats fit into that equation.

TWILLEY: And those fats make up a lot of our industrial fat, they’re used in all kinds of processed foods, from ice cream to chocolate bars to packaged cookies.

ALEXANDER: Those customers are really important for us getting to impact and getting to scale. That’s like if we want to make it so that we don’t, you know, deforest like one more single acre of tropical rainforest. Right? Like those are the partners that we have to get on board. So we—our kind of first commercial facility is targeted to be able to compete directly on cost with milk fat or cocoa butter. So these are kind of higher priced, but still commodity fats and oils.

GRABER: The idea is if Savor can compete on price with milk fat and cocoa butter and get those clients, they can use that investment to scale and become less expensive, at which point they hope to be able to compete with palm oil, which is even cheaper. While it might be a great idea to eat fewer of the kind of processed foods that contain these oils, in reality we’re eating more of them. And we’ve talked about how incredibly destructive palm oil is on a previous episode. So replacing that in our food system has a lot of potential.

TWILLEY: Overall, making food from air has a lot of potential benefits. Clearly in niche situations, like outer space or the battlefield, it could be key to survival, but for the rest of us, it’s an industrial solution that could make our industrial food supply more sustainable. Kathleen and some academic colleagues recently published a paper in a peer-reviewed scientific journal trying to quantify some of those potential environmental wins.

GRABER: One benefit is in terms of greenhouse gas emissions. Making Savor’s fat does take electricity to power all those processes, and how their air fat compares to, say, palm oil depends on whether they use renewable energy or not.

TWILLEY: But for Savor’s fat, the greenhouse gas emissions are already pretty much the same or lower than palm oil, even if they’re just using electricity from the US grid. If they can make Savor using renewable energy, and pull more carbon dioxide out of the air as one of their ingredients, then the emissions for each stick of butter could be negative.

GRABER: When it comes to the land use question—the issue that caught her co-founder’s eye when he was looking out of the airplane—the savings are dramatic. It takes only about two percent of agricultural land to make a calorie of Savor as compared to a calorie of palm oil, which could lead to thousands and thousands and thousands of acres of forests being hopefully protected or rewilded.

TWILLEY: But, as we’ve said, if you’re using gases from the air to feed a microbe to make something like Juha-Pekka’s Solar powder, that process of dissolving all the gasses into the water your microbe lives in is very very energy-intensive.

PITKÄNEN: So indeed, electricity is our main ingredient. Well, it basically comes from the grid. And that is of course the main input into our process.

GRABER: In a different paper analyzing the benefits and challenges of this new technology, the authors say that if the entire electrical grid all over the world was used to feed protein-rich microbes like SoFi, all of that energy would only produce about half the calories that humanity needs. Obviously we wouldn’t do that, and also we don’t get all our calories from protein. But this gives you a sense that it takes a lot of energy to make this work.

TWILLEY: Not only is it something we would never do, but also it’s not even something we’re close to being able to do. Juha-Pekka told us his pilot plant can only make about 1,000 pounds of protein powder per day. That’s not nothing, the company calculates it would take 50,000 hens to produce the same amount of egg protein, but it’s only enough protein for roughly 5,000 people, at our current consumption levels.

GRABER: It also means he’s not at the scale where he can compete on the market yet. Solar’s protein powder is still niche and in development—they need to eventually have a factory that can put out about 3,000 tons a year to be competitive.

PITKÄNEN: Because it basically then enables us to be there in the, like a whey protein price point, maybe even a little less.

TWILLEY: Of course, for now, Juha-Pekka and Kathleen are still at very early days; they’re still getting approval to sell their products and their factories are still pilot plants. But they are planning to grow.

ALEXANDER: We are scaling up. You know, we’ve made it through our first regulatory approval. We are, you know, in, in some restaurants and, you know, have these early commercial partners.

GRABER: It’s not necessarily going to be in the super-near future, but they both think that you’ll be able to find these food from air products in your grocery store some day. Juha-Pekka hopes his pathway forward will be like the company Quorn, they make vegan patties out of a fungus, we here at Gastropod love them.

PITKÄNEN: I’ve been thinking about it and kind of looking into the path.

TWILLEY: The path of Quorn has been long. They started looking for their fungus in the 1960s, they found it in 1967, and then Quorn products didn’t go on sale in supermarkets until all the way in 1985. Nearly two decades later.

PITKÄNEN: So that is—in my view, that is a realistic scenario. So for Solar Foods.

GRABER: Okay, so maybe you shouldn’t be anxiously checking their website to see when they’re showing up at a store near you. But this technology isn’t as out there as it seems.

ROMAN: I don’t know. It’s crazy, but like, everything that is in the early stages is, you know, it looks crazy and ridiculous. And I, I think it’s going to get there. I know it’s going to get there. And it’s going to be part of the buffet of choices that people will have to feed themselves.

TWILLEY: The other thing that’s important to remember is that buffet. Because even in a couple of decades’ time, when your Oreos are made with Savor rather than palm oil, and your protein bar contains Solar powder rather than whey, it’s not like you’ll be dining exclusively on food made from air. Unlike Marcellin and Daniel Berthelot, nobody today thinks food made from air will be all of the food we’ll ever eat.

ALEXANDER: We actually think that agriculture is a very—you know, is like going to be part of how we feed humans for a long time. Like, we don’t have a way of making you a tomato. And we don’t want to live in a world that doesn’t have tomatoes.

[MUSIC]

GRABER: Two quick exciting things for you listeners: one, we have some new T-shirts for sale! Just to let you know, this is not a fundraiser for the show, this is just something you’ve all asked for so you can show your love around town. You can find them at gastropod.dashery.com or on our website gastropod.com. Be sure to check out the different fit and style options for each tee-shirt to make sure to get the best one for you!

TWILLEY: And the second thing: we want your questions! We’re making another of our favorite Ask Gastropod episodes, and they’re fuelled by the things you want to know. So email us at contact at gastropod dot com with whatever you’re wondering about.

GRABER: Thanks this episode to Bill Gourgey, Kathleen Alexander, Juha-Pekka Pitkänen, Collin Timm, and Monsi Roman, you can find links to their companies and research at our website, gastropod.com, and thanks as always to our amazing producer Claudia Geib.

TWILLEY: We’ll be back in a couple of weeks with another glorious episode for your listening delight. Till then!