“Many microorganisms are high in protein and could be used as sources of protein food for humans or animals. However, the economics of producing single-cell protein are unsatisfactory when compared with protein production from meat or grain.
The most important food produced microbially is the mushroom, which is produced not for its protein, but for its flavor”.
By: Thomas D.Brock and Michael T. Madigan
In: Biology of Microorganisms
Printing: Prentice Hall, Englewood Cliffs, New Jersey 07632. 1991; p. 385.