Power-to-Protein as a Novel Protein Value Chain

Global food supply chains are under constant transformation due to changing diet habits, climate change, economic constraints, and technological advances. At present, there is a strong interest in developing new resilient protein value chains that deliver functional and nutritional proteins that are also economically viable. ‚Power-to-protein’ refers to an approach that utilizes electricity to produce green hydrogen that is then utilized as a feedstock to cultivate protein-rich biomass using hydrogen-oxidizing bacteria. This decouples protein production from agricultural-based feedstocks.

This talk will introduce the technology behind the power-to-protein approach. The required ambient pressure bioreactor design will be presented. The reactor is based on a temperature-controlled double-jacketed glass vessel that is equipped with two individual sparger units that introduce the gases (H₂, CO₂, O₂) into the mineral medium. The bioreactor unit is equipped with an air-driven overhead stirrer to maximize the mixing efficiency and gas transfer. Gas purging units are also included in the design to ensure that the off-gas stream is below the flammability limit before leaving the headspace of the bioreactor. Based on this reactor design, relevant heterotrophic and autotrophic growth curves will be discussed that show cultivation parameters of promising hydrogen oxidizing bacteria for food applications. The discussion will conclude with a vision of the design of such a new protein value chain and the relevant challenges will be presented.