Making the case for edible microorganisms as an integral part of a more sustainable and resilient food production system

Edible microbial biomass derived from bacteria, yeasts, filamentous fungi or microalgae is a promising alternative to conventional sources of food and feed. Microorganisms are a good source of protein, vitamins and, in some cases, also contain beneficial lipids. The ability of microorganisms to use simple organic substrates for growth permits industrial-scale cultivation of edible microbial biomass in geographical locations that would not compete with agricultural production. Only a handful of microbial products are currently available for human consumption. The use of microbial biomass for animal feed is limited by access to low-cost growth substrates and competition from conventional feed sources such as soy and fishmeal. At a time when the global food production system is threatened by the effects of climate change, the production of edible microorganisms has the potential to circumvent many of the current environmental boundaries of food production as well as reducing its environmental impact. Photosynthetic microorganisms such as cyanobacteria and microalgae can be cultivated for food and feed independently of arable land. In addition, recent technological developments in atmospheric carbon dioxide (CO2) capture, extraction and catalytic conversion into simple organic compounds can be used for cultivation of edible microbial biomass for food and feed in a manner that is wholly independent of photosynthesis. The future possibilities, challenges and risks of scaled-up production of edible microbial biomass in relation to the global food system and the environment are discussed.