Protein from CO₂ is at the centre of a new Danish project that aims to produce protein-rich food ingredients without using additional farmland. React Foods, a spin-off based on research from Aarhus University and international partners, plans to use microorganisms, carbon dioxide and hydrogen produced with renewable electricity to grow a protein-rich yeast biomass. The technology will now be tested and scaled at pilot facilities in Viborg, but it is still far from producing a commercial food product.
The Copenhagen-based company has received DKK 4.2 million (about €562,000) from the BioInnovation Institute. According to Aarhus University, React Foods builds on research carried out by Aarhus University, Stanford University and the University of Tübingen in cooperation with the Novo Nordisk Foundation CO₂ Research Center (CORC).
How protein from CO₂ is made
The process proposed by React Foods has two main stages.
First, microorganisms receive CO₂ and hydrogen produced using renewable electricity. They convert them into acetate, a compound that is also the main component of vinegar. In a second stage, the acetate is used to feed yeast. As the yeast grows, it produces a biomass with a high protein content.
The result is not yet food. The biomass would need further processing to obtain ingredients with the taste, texture and other characteristics required for use in products such as protein bars or as alternatives to some egg and dairy proteins.
React Foods will use the pilot facilities at AU Viborg, Aarhus University’s research campus in central Denmark, to connect the different stages into a single system. The immediate objective is therefore not mass production, but to establish whether the technology can work efficiently as an integrated process and whether further scaling is realistic.
The main question is how much energy it needs
Producing protein without additional farmland does not mean producing it without significant inputs. One of the most important is electricity.
Hydrogen has to be produced, and React Foods says it intends to use hydrogen generated with renewable energy. This means that the environmental performance and eventual cost of the process will depend partly on how much electricity is required and where that electricity comes from.
React Foods has not published figures for the energy consumption, production yield or expected commercial cost of its own integrated pilot process.
There is, however, relevant research from the same scientific field. A peer-reviewed study published in Proceedings of the National Academy of Sciences in August 2026 and co-authored by React Foods co-founder Largus Angenent examined an industrial-scale model in which CO₂ and renewable electricity are converted into acetate and then used to produce protein-rich yeast biomass. The study, listed by Aarhus University found that electricity prices and the energy required for water electrolysis were among the main factors affecting production costs.
The study modelled a system rather than the future React Foods plant, so its estimates cannot be treated as expected results for the company. It nevertheless highlights one of the questions that the Danish pilot will eventually have to address: whether producing protein from carbon and electricity can become efficient enough to work outside the laboratory.
Less farmland is part of the appeal
The main advantage claimed for the technology is its limited dependence on agricultural land.
React Foods says protein production based on fermentation could complement existing food chains while being less exposed to extreme weather and without requiring additional arable land. That could be particularly relevant in Denmark, where the use of agricultural land has become part of the country’s broader climate and environmental transition.
Under the political agreement implementing Denmark’s Green Tripartite (Den Grønne Trepart), around 250,000 hectares of new forest are planned, while about 140,000 hectares of carbon-rich lowland soils and adjacent areas are to be taken out of their current use. The agreement explicitly combines changes in land use with efforts to develop more sustainable and land-efficient agricultural production.
React Foods is not presented as part of that agreement. But technologies capable of producing some food ingredients with little or no additional farmland fit into the wider question Denmark is facing: how to maintain food production while allocating more land to climate measures, forests and nature.
There is still no food ready for the market
The project also faces a regulatory stage before any ingredient could reach European consumers.
Under the EU’s Novel Food Regulation, companies must establish whether a food falls within the novel food framework before placing it on the European market. The European Commission specifies that foods derived from microorganisms or new production processes may qualify, depending on factors including whether they were consumed to a significant degree in the EU before May 1997.
It is therefore too early to say exactly which authorisation route a future React Foods ingredient would require. The final composition and production method would first have to be established.
For now, React Foods has a technological concept, research behind it and funding for pilot-scale development, but not a commercial food product. The coming tests at AU Viborg are intended to show whether the individual biological processes can be combined efficiently enough to justify further investment and industrial partnerships.
If that works, the Danish project could provide another route for producing protein in a food system increasingly constrained by land use and climate targets. Before that happens, however, React Foods still has to demonstrate the factors that matter beyond the laboratory: energy demand, production efficiency, costs, environmental performance and regulatory viability.
