Just add renewable energy: start-ups turn CO2 into ‘butter’, fake meat and more

The food industry is constantly changing. As tastes evolve and diets are rewritten, producers and shops promote previously little-known products and ingredients. From ‘superfoods’ and once-exotic but now familiar specialties such as halloumi, to plant-based alternatives to milk and meat products, our modern shopping baskets change with the latest trends as they once did with the changing of the seasons.

The next dish to turn up on your dining table could have an unlikely main ingredient – carbon dioxide (CO₂). A handful of companies around the world are turning the industrial by-product and environmental pollutant into products including butter-like spreads, milk alternatives, and even fake meats.  

Of course, CO₂ is already used as a food additive, making the bubbles in soft drinks and regulating acidity in some products. But the new process engineering-based projects are doing something different, using the gas as one of the principal components to make basic ingredients, which can then form the basis of complete meals.

By using CO₂, companies aim to reduce the environmental impact of food production. If they commercialise successfully, they could find some other benefits.

It’s a gas

Powered by renewable energy, a new process unveiled yesterday (12 September) by researchers at the University of Tübingen in Germany has particularly sustainable credentials. The team produced a micronutrient-enriched protein alternative from microbes by feeding them “nothing much more” than hydrogen, oxygen, and CO₂.

“This is a fermentation process similar to how you make beer, but instead of giving the microbes sugar, we gave them gas and acetate,” said corresponding author Largus Angenent.

“We are approaching 10bn people in the world, and with climate change and limited land resources, producing enough food will become harder and harder. One alternative is growing proteins in bioreactors through biotechnology, rather than growing crops to feed animals. It makes agriculture much more efficient.”

The team designed a two-stage bioreactor system that produces yeast rich in protein and vitamin B9. The researchers found that protein levels in their yeast exceed those of beef, pork, fish, and lentils. After treatment to remove certain compounds prior to consumption, they said it would provide 41% of a person’s daily protein requirement from 85g or six tablespoons.

One of the most prominent players in the CO₂ food space is Finnish start-up Solar Foods, which opened the world’s first commercial-scale production facility in April. The company’s Solein protein is also produced by feeding a micro-organism with CO₂, along with hydrogen and oxygen, and a small amount of nutrients. The bioprocess resembles winemaking, the firm said, with the CO₂ and hydrogen replacing sugar as the sources of carbon and energy respectively.

The result is a yellow powder that Solar Foods says can be used with a “wide range” of traditional ingredients. It has already been used as a novel ingredient for limited-edition products in Singapore, including a snack bar and a chocolate ice cream.

Growing a kilogram of Solein requires approximately 1% of the water and 5% of the arable land that growing an equivalent amount of plant protein would, the company said, creating only a fifth of the CO₂ emissions in the process. The new manufacturing facility will ramp up annual production to a maximum of 160 tonnes.

“We will be able to deliver quantities that allow food producers for the first time to create large batches of Solein-powered products. While we have been able to offer consumers a small taste, finding a Solein-based food in your local supermarket has not been possible. Soon it will be,” said company CEO and co-founder Pasi Vainikka.

Spreading it on thick

Other projects have a different focus. Bill Gates-backed start-up Savor, for example, is making a butter alternative out of fats produced with CO₂, using heat and hydrogen to form hydrocarbon chains that are then blended with oxygen. Its next products will include milk, cheese and fake meat.

New CO₂-based products could enable a completely different approach to making food, in a time when climate change and population growth are putting intense pressure on traditional harvests.

By “uncoupling land use from farming”, the team from the University of Tübingen ultimately hopes to free up space for conservation. Rather than competing with farmers, the researchers hope the technology will help them “concentrate” production of vegetables and other crops.

Solar Foods’ factory demonstrates that it is possible to grow protein “from start to finish under one roof”, Vainikka said, “even in the harsh Northern conditions of Finland”. Without reliance on weather or climate, the company suggests, its product could be produced in deserts, the Arctic, or even in space.

For now, factory production for supermarket sales seems like the logical next step. Close attention will be needed to ensure products are healthy – or at least not much more unhealthy than the products they replace. Companies will also likely face opposition from the meat industry, which has opposed other protein alternatives already on the market.

Of course, whether the products are successful or not will come down to two key metrics – how expensive they are, and what they taste like. Early reports are promising, so watch this space.

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