Protein source · 07
Gas (air) fermentation
Some microbes can use gases such as hydrogen or carbon dioxide as inputs, producing biomass that may become feed or food.
Microbes fed on gases and energy
Gas fermentation grows microorganisms using gaseous feedstocks rather than conventional crops as the main carbon or energy source. Depending on the process, inputs can include carbon dioxide, hydrogen, oxygen and nitrogen.
This route has attracted interest because it may produce protein without relying on agricultural land for its primary feedstock. But “from air” is shorthand, not a complete description: the gases need to be sourced, hydrogen needs to be made, and the process requires energy and equipment.
The climate result depends heavily on how electricity and hydrogen are produced. A full assessment also needs to consider nutrient inputs, downstream processing, scale and what the resulting protein replaces.
This is an editorial overview, not a product-specific life-cycle assessment. See our editorial standards for how claims and sources are handled.