By Harold McGee
Mycoprotein is a 20th-century invention, an edible form of the normally useless underground hyphae of a common fungus, Fusarium venenatum. A strain of the fungus originally taken from a field in Buckinghamshire, England, is grown in a liquid medium in a factory-scale fermenter. The resulting mass of hyphae is harvested, washed, and rapidly heated. This produces microscopic fibers that are rich in protein and about 0.5 mm long and 0.003–0.005 mm in diameter, or about the dimensions of muscle fibers in meat. This essentially tasteless mycoprotein (from myco-, “related to fungi”) can then be manufactured into meat substitutes and a variety of other food products.