Rima Gnaim, Hakimi Kassim, Lisa Neidhardt, Thomas Gassler, Rodrigo Ledesma‐Amaro
Microbial biomass fermentation, in which microbes are cultivated to produce nutrient-dense biomass, offers a scalable route to sustainable protein production with low land, water, and greenhouse gas footprints. However, its shift from a speciality to a mainstream food continues to be difficult. Here, we move beyond technological overviews and propose a three-phase adoption framework: novelty barrier, early trust-building, and mainstream normalisation. This framework organises techno-economic, regulatory, and infrastructural barriers into a single trajectory. We trace single-cell proteins' rise, decline and resurgence, map engineering and policy enablers by phase, and outline levers to move microbial proteins into resilient food systems.