Protein Out of Thin Air: OHB to make revolutionary technology with Solar Foods for future astronauts

Bremen, 4 November 2025 – How will astronauts survive on future long-duration missions to the Moon or Mars – without resupply from Earth? One possible answer doesn’t grow in fields but is created through fermentation of a bacterial culture that produces a nutrient-rich protein. Together with Finnish food tech pioneer Solar Foods and under the patronage of the European Space Agency (ESA) OHB System AG is bringing this vision into space: the project HOBI-WAN (Hydrogen Oxidizing Bacteria In Weightlessness As a source of Nutrition) aims to test this innovative method for the first time in microgravity aboard the International Space Station (ISS). The study phase has now begun and is funded by ESA through its Terrae Novae Exploration Programme.

Fermentation Instead of Farming

The technology is based on a fascinating principle: A nutrient solution containing a bacterial culture is fed in a bioreactor with gaseous hydrogen, oxygen, and CO₂ which are being produced directly by the crew or through the life support system of the Station. Unlike on Earth where a pinch of ammonia is used as the nitrogen source, in space urea serves as the nitrogen source for protein synthesis. The bacteria convert these substances through fermentation into Solein® – the name of a protein-rich powder that requires neither farmland nor sunlight. The experiment will be housed in a standard middeck locker, a container that has been used on the ISS for many years. It will include all components required for the bioreactor, such as an incubator, sensors, control units, and systems for sample extraction.

“More Than Just a New Protein Source”

“Since the European Columbus module was commissioned, OHB has been developing, operating, and maintaining scientific payloads for the ISS for over two decades. Our deep understanding of the ISS environment, combined with our experience in life support systems and scientific experiment platforms, makes us the ideal partner to bring Solar Foods’ technology into orbit – and we are very much looking forward to this collaboration,” says Jürgen Kempf, HOBI-WAN Project Manager at OHB. But the mission goes far beyond testing a novel protein source, Kempf adds: “We are exploring how to sustainably support human life in space. The insights we gain here could also help address global challenges on Earth – such as resource scarcity and food security. We are proud to contribute our expertise to a project that connects space innovation with planetary sustainability.”

Phase One: A Ground-Based Science Model

The first eight-month study phase will focus on developing a ground-based science model. The goal is to validate the core processes and determine whether the production of the protein-rich powder can also function under microgravity conditions. Solar Foods’ bioprocess technology must be translated into a compact, autonomous system that can operate reliably in space. For example, special cartridges must inject gases without any liquid escaping – a critical aspect, especially given the explosive potential of hydrogen and oxygen mixtures. The experiment box will contain three separate experiments, and astronauts will be required to extract samples during the mission. Thanks to its experience with previous Biolab experiments, the Human Spaceflight Department at OHB knows which materials and components are best suited for use in space.

“We are truly happy that we get to collaborate with OHB. Their expertise of evaluation and certification especially with respect to mandatory safety requirements will help us design a system that is suitable for the space environment, provides the needed data and most importantly can be safely operated onboard a manned space station”, says Arttu Luukanen, Senior Vice President Space & Defence at Solar Foods.

Launch to the ISS 

If the first phase is successful, the next step will be the development of a flight model, with the goal of launching it to the ISS. HOBI-WAN is part of a growing European commitment to closed-loop systems – technologies that provide water, air, and food in a self-sustaining cycle. The results of this project are expected to benefit not only space exploration but also sustainable food solutions on Earth – especially in regions with limited resources.

The project (ESA contract No. 4000149559/25/NL/ATC) is carried out under a programme of, and funded by, the European Space Agency. The views expressed in this press release can in no way be taken to reflect the official opinion of the European Space Agency.