Foods and Feeds from Fungi

Abstract

Current interest in the synthesis of food by microorganisms arises from three main considerations: (a) the critical need for food, and in particular for protein, that exists in many parts of the world; (b) the economic advantages of microbial elaboration of foods or vitamins from relatively inexpensive raw materials; (c) the reduction of the cost of disposal of fermentable factory wastes.The reader is asked to accept for the present purpose an interpretation of the titular word "fungi" to include mycelial forms of the Eumycetes (molds), the yeasts, and bacteria. Their potential contribution to the world's food supply will be discussed with regard to the synthesis of fat and protein and of other substances of dietary value; the specific amino acid and fatty acid content of fungal proteins and fats; the nutritional value of fungal foods; their toxicity; the microorganisms studied; and the technology of production from the point of view of basic factors related to the organism, its environ ment, and commercial substrates.The basis of commercial food synthesis by fungi is the high degree of efficiency of these organisms in using energy from cheap carbohydrates to convert elementary nutrients into protein and fat [Foster (78)]. The potential significance of such efficiency is evidenced by the calculation that the produce from one acre of arable land can be converted into ten times as much pro tein by fungi as by animals [Robinson (188)]. Yield data are tabulated by Dunn (62).

Physiology of Wood-rotting Basidiomycetes

“…Our preliminary results indicated that, while these fungi probably did not contain a toxic principle, the mycelium was not nutritionally adequate as a sole source of food. Similar results have been observed with other kinds of fungi which have been assessed for nutritional value (see Thatcher, 1954).…”

“…Submerged-culture mycelium of another mushroom-the edible morel, Morchella hortensis (an Ascomycete)-has been shown in our laboratory (Koda, 1951) to contain the same amino acids as does P. palustris, although in different proportions. References to other papers on various chemical constituents of higher fungi, including woodrotting Basidiomycetes, are given by Ralph (1949); the on September 3, 2020 by guest http://aem.asm.org/ Downloaded from distribution of vitamins in microorganiisms is reviewed by Van Lanen and Tanier (1948) and by Thatcher (1954).…”

“…Reasons for the current interest in the synthesis of food by microorganisms, as well as a review of the technical literature, are given by Thatcher (1954). 'Many factors, biologic and economic, enter into the question of what kinds of microbes may be of practical use.…”

“…As regards nutritional value, the chemical composition and vitamin content of relatively few kinds of fungi have been reported (see review by Thatcher, 1954). Strains of yeast have been studied most extensively (Dunn, 1952), bacteria and higher fungi to a lesser extent.…”

Physiology of Wood-rotting Basidiomycetes

“…Submerged-culture mycelium of another mushroom-the edible morel, Morchella hortensis (an Ascomycete)-has been shown in our laboratory (Koda, 1951) to contain the same amino acids as does P. palustris, although in different proportions. References to other papers on various chemical constituents of higher fungi, including woodrotting Basidiomycetes, are given by Ralph (1949); the on December 13, 2020 by guest http://aem.asm.org/ Downloaded from distribution of vitamins in microorganiisms is reviewed by Van Lanen and Tanier (1948) and by Thatcher (1954).…”