Air-Derived Proteins: The Next Step In Circular Food Economy

Air-derived proteins are an ingenious solution to address the growing gap between nutritional requirements and available resources. An extension of cellular agriculture, the microorganisms involved in this process use atmospheric gases as raw material to produce edible proteins and other supplements. It is an emerging research area that holds the potential to enhance the production efficiency of advanced farming concepts like vertical farming and urban agricultural systems. Unlike other alternative proteins, the production of air-based proteins requires minimum land and water resources, implying that their wide application will reduce pressures on arable land while lowering the environmental footprint of food production to a considerable extent. 

Basic Principle Behind Air-Derived Proteins

Air-based protein production relies on three kinds of bacteria: methanotrophs, hydrogenotrophs, and carboxydotrophs. While hydrogenotrophs and methanotrophs are promising constituents of SCP (single-cell protein) production, the carboxydotrophs are essentially included from a sustainability perspective. There are four fundamental reasons for the selection of these three bacteria: 

• Heat generation and oxygen absorption for fermentation
• Stable genome and morphology throughout the process
• The end-product is 60-70% protein
• Easy recovery and auto-purification ability on the yield

The fraction of gas holding carbon monoxide, hydrogen, and methane supplies energy in the form of an electron, while oxygen completes the reaction by finally accepting that electron. The carbon dioxide remains fixed during this reaction, which makes it the most plausible method of capturing atmospheric carbon for sustainable protein synthesis. Therefore, hydrogen reacts with oxygen in the presence of carbon dioxide, producing biomass and water, just like oxygenic photosynthesis. 

Their overall reaction can be thus denoted as: 

H2 + O2 + CO2 → Biomass + H2O 

When the same reaction is carried out via electrolysis: 

H2 + O2 + Energy → Biomass + H2O

The use of hydrogenotrophs is a standard practice in this context due to their survival ability. From Antarctica to superhot hydrothermal vents, they can outlive every harsh condition. 

Once harvested, the cell biomass is put through downstream processing and purification. 

The most significant advantages of air fermentation are a relatively shorter generation timeline and compatibility with multiple fermentation technologies, including solid-state, semisolid, and submerged fermentation methods. 

Any Challenges?

Despite their high scores on the time, sustainability, and availability scales, air-derived proteins are being held back due to a few roadblocks. 

• Production Costs: Fermentation is a sensitive process that needs to be carried out under optimal conditions. Since the primary reaction in this process is bacteria, the conditions need to be regulated for consistent and safe production. Therefore, the budget is very high, especially for the harvesting phase, countering the easy availability of raw materials to an extent. 

• Safety: Axenic conditions are necessary for fermentation to prevent unwanted contamination. Low-quality ingredients bear a high risk of contamination for SCP, placing more pressure on producers for high-quality ingredients and purification processes. Also, SCP’s high nucleic acid content limits its application in food. It must be brought under 2% of the total mass to make it suitable for human consumption. The air-derived protein has 6-10% nucleic acid, which may lead to health issues like kidney stones and gout. 

•  Regulatory Hurdles: Companies looking for market entry and growth in this segment need to overcome several regulatory hurdles. In the EU, the EFSA framework needs comprehensive navigation strategy, while in the US, companies must achieve GRAS (Generally Recognized As Safe) status to market their products. Also, there is a hierarchy of labeling, idensity, cross-border compliance, and public perception legal frameworks that need to be worked upon. For instance, Solar Foods, a Europe-based air protein company, has received GRAS status in the US but is still navigating the EFSA to get started in the EU. 

Commercial Ecosystem 

A limited number of startups are marketing or developing air-derived proteins for now. The most notable ones include: 

• Solar Foods: A Finland-based startup that recently raised € 8 million in a Series B investment. It uses hydrogen fermentation to turn CO2 into edible protein (Solein). The company has garnered considerable attention for its scalable and sustainable approach. 

• Air Protein: A US-based company using precision fermentation to convert carbon dioxide into protein. Recently raised $32 million in funding. 

• NovoNutrients: This company generates protein flours by employing hydrogen—and carbon-oxidizing bacteria. It last secured $9 million in equity funding. 

• Calysta, A leading sustainable protein solutions provider, uses gas fermentation to produce FeedKind, a protein used in animal food. 

• Arkeon Biotechnologies: It specializes in turning carbon dioxide into valuable resources. It is turning CO2 into all essential 20 amino acids by leveraging aechaea. The highlighting part is that the production takes a single step. The company last raised €6.5 million in funding. 

The Future Outlook

A comparative analysis of its pros and cons concludes that the results favor its pros. With the evolving technological developments in fermentation, harvesting, and downstream processing, strategic applications of air-derived proteins will likely take a leap in the near future. It presents a compelling investment opportunity for FoodTech and Agtech VCs looking to redirect their efforts towards circular economy and sustainable production methods. They may look for strategic partnerships to gain a competitive edge and profitability. However, due diligence is necessary due to varying regulatory compliance, consumer acceptance, and supply chain management efficiency.