From air to your plate: tech startups making food from atmospheric CO₂

Food startups based in the United States and Europe are using carbon dioxide to create food. Californian company Air Protein has raised $107 million to create steak and scallop products from CO₂. In June, the Bill & Melinda Gates Foundation and the Novo Nordisk Foundation invested $29.2 million into a Novozymes and Topsoe project that is using CO₂ to produce proteins for human food without involving agricultural land. Others are stepping into the CO₂ food arena as well (Table 1). For Air Protein founder Lisa Dyson, scaling up protein production to feed 9.8 billion people by 2050 must entail an environmentally responsible approach: “How can we make more food in a way that is climate positive?”

Making food with microbes: Air Meat chicken protein takes only hours to grow.
Credit: Air Protein

Agriculture is a huge contributor to climate change, and the problem is only likely to grow. To mitigate the impact of food production, Air Protein plans to replicate photosynthesis in the lab by placing oxyhydrogen microbes in a reactor to make macro- and micronutrients including proteins, fats, carbohydrates and vitamins.

NASA subject matter expert in biotech Bruce Link from the Kennedy Space Center says that although photosynthesis by carbon-fixing plants is the main route to food production, there are alternatives. “[Photosynthesis] can be done either by life forms or catalytically,” says Link. “If you are in an environment where sulfur or hydrogen are abundant, you can convert the CO₂ into chains of carbon, which are basically oils.” The notion of creating food from CO₂ has been gaining momentum. The European Innovation Council has just sunk $5.5 million into a project called Hydrocow: several European partners will work together to produce milk protein for human consumption made in the lab by anaerobic bacteria. The consortium includes the University of Groningen in the Netherlands, the RWTH Aachen University in Germany, Swiss biotech company FGen in Basel and Solar Foods located in Lappeenranta, Finland. Their goal is to genetically engineer microbes that feed on CO₂ and hydrogen to secrete β-lactoglobulin, the major protein in whey from cow’s milk. Although milk has a multitude of other components, the consortium will start with β-lactoglobulin as it constitutes approximately 65% of the total whey protein.

The Finnish company Solar Foods is already producing food from CO₂. At a Mediterranean restaurant on Singapore’s east coast, diners can order scoops of chocolate gelato and fresh pasta manufactured with the microbially made protein Solein. The protein is created in a similar way to the proposed Hydrocow protein. The microbe, which has not been genetically modified, is an anaerobic Xanthobacter found on a Finnish beach. It is placed in a bioreactor with CO₂, hydrogen and salts. The end product is dried to become a turmeric-colored powder which the company calls Solein, with a protein content similar to that of steak. If liquid is added to the powder, it can be used as a binding agent and an alternative to eggs in food production.

Solar Foods CEO Pasi Vainikka says: “The technology gives humankind [the chance] to bypass photosynthesis and land use, and that has never happened before.” A life-cycle assessment comparing this new type of protein production found the environmental impact to be 47–99% lower with hydrogen-oxidizing bacteria than with traditionally produced peas or nuts. Solar Food claims that producing 1 kilogram of Solein emits 0.2 kilograms of CO₂-equivalents, compared with 100 kilograms produced by beef rearing and 10 kilograms to produce chicken meat. When Solar Foods’ new factory opens in Finland at the end of the year, it expects to produce 100 tonnes of Solein a year.

Other big funders — the Bill and Melinda Gates and Novo Nordisk Foundation s — have stepped up to support CO₂-driven fermentation platforms. Each is funding half of the activities of a new consortium that combines biotech and chemical engineering expertise from Danish companies Novozymes, of Bagsværd, and Topsoe, located in Lyngby, with Washington University, St. Louis and the Novo Nordisk Foundation CO₂ Research Center at Aarhus University in Denmark. The aim is to investigate biological and electrochemical processes that turn CO₂ into acetate. They will use it to create a mycoprotein that can substitute for meat.

Novozymes will spend the next two years proving the technology, then build a flagship facility so it can scale. Claus Crone Fuglsang, CSO of Novozymes, says: “Scaling to produce cost efficiently on acetate at a high-quality level is the primary challenge. The protein itself, or the food products it’s included in, must be consumer palatable, nutritious and affordable.”

Austrian biotech company Arkeon, based in Vienna, is also using CO₂-consuming microbes to help create protein. It is using Methanothermobacter microbes that are found in hot springs or lakes to create protein ingredients. The company expects to use one-step fermentation, without genetic engineering, to produce 20 amino acids (including the eight essential amino acids needed by the body) by placing this microbe in a bioreactor with carbon dioxide and hydrogen. Taking carbon from CO₂ and energy from hydrogen, the microbe spits out the amino acids. The resulting nutrients will be sold to food companies so they can use them in sports drinks, protein bars and plant-based meat alternatives. The company is now ready to leave the laboratory and scale up.

Michael Mitsakos, Arkeon’s co-founder says: “Our carbon-uptake approach is to ‘industry-capture’ the CO₂ directly from CO₂-producing sites … therefore preventing it from being emitted into our atmosphere.” They are in talks with potential partners regarding the CO₂ supply for their bioprocesses. The team is now applying for regulatory approval to sell its products in Europe and the United States.

Even eschewing microbial fermentation, it is possible to capture atmospheric CO₂ and turn it into a product. A startup in New York is already serving vodka made from CO₂ to customers. Biochemist Stafford Sheehan joined marketing specialist Gregory Constantine in August 2017 to launch Air Vodka. The reaction first splits water into hydrogen and oxygen gas; they then take the hydrogen gas, mix it with CO₂, and pass that over a catalyst. This hydrogenates the carbon dioxide; the resulting compound can be transformed into chemical products such as alcohol. The company recently raised $30 million in a series A, and has now expanded its product line to include jet fuel.

It also created a single-cell protein, Candida Utilis, from CO₂ for the NASA Deep Space Food Challenge competition, which is designed to help feed a crew of four on a three-year mission. In work that is still unpublished, they made sugar with CO₂ (which would be exhaled by astronauts) and then used it to feed yeast. The resulting tofu-like protein can be added to shakes or rolled out flat to create pasta or tortillas. The Air Company is now scaling up from a demo plant. “What I’ve learned from this whole process is discovering new chemistry is way easier than scaling it up and making it commercial,” says Sheehan.

Unlike crops, which rely on free sunshine to grow, CO₂ food producers need to invest in expensive equipment, such as photovoltaic panels to help reap power. And direct air capture also doesn’t come cheap. But it won’t always be the case, says Dawid Hanak at the Net Zero Industry Innovation Centre at Teesside University in the United Kingdom. The equipment and the chemical materials that bind the CO₂ currently costs about $600 for every tonne of CO₂ removed. “Costs are expected to drop to between $125–335 per tonne of CO₂ in the 2030s, similar to how the cost of solar energy fell over time,” says Hanak.

Sheehan believes sinking CO₂ into food can make a dent in the world’s carbon emissions. “We can definitely do it. It’s going to take time and a lot of investment as all the infrastructure in the world doesn’t change overnight,” he says. “If we don’t have sustained effort, it’s not going to happen. We need sustained effort over decades.”