Single Cell Protein (SCP)

Improving crop plants, whether by breeding or tissue culture, is one route to feeding a growing population; producing more protein without growing a crop plant at all is a second, complementary route, and this is exactly what Single Cell Protein does.

What is Single Cell Protein?

Conventional agriculture struggles to keep pace with the combined food and protein demand of a still-growing human population, particularly as diets shift toward more meat, which is itself an inefficient way to convert grain into food energy -- it typically takes several kilograms of grain to produce just one kilogram of meat through animal farming, since most of the grain's energy is lost as it moves up the food chain. Single Cell Protein (SCP) addresses the resulting protein shortage directly: it is protein-rich biomass obtained by culturing microorganisms -- bacteria, yeasts, fungi or algae -- on a large, industrial scale specifically as a source of protein for human or animal nutrition, bypassing conventional crop and livestock farming altogether.

Organisms used and why they are attractive

A range of microorganisms are cultured for SCP, including the blue-green alga (cyanobacterium) Spirulina, the bacterium Methylophilus methylotrophus, various yeasts such as Saccharomyces cerevisiae, and filamentous fungi such as Fusarium venenatum, which is processed into a well-known commercial mycoprotein food product. Microorganisms are especially well suited to this role because they reproduce and accumulate biomass extremely rapidly compared with any crop plant or farm animal, can often be grown on comparatively cheap and abundant substrates (including agricultural or industrial waste materials, and, for Spirulina, even waste water enriched with nutrients), require far less land and water per unit of protein produced than conventional farming, and yield a biomass that is characteristically very rich in protein along with useful vitamins, minerals and fats.

Significance …