Grain Spawn – “Grain Spawn” is produced in a laboratory under clean room conditions. Live, sterile mycelium is inoculated into sterilized grain, such as rye, wheat, rice, millet, or sorghum. After a growth period of approximately 21 days, the grain is fully coated and colonized by the mycelia and is ready to use as seed in the cultivation of mushrooms.
Hypha – A “hypha” is a very fine tube-like filament formed from the germination of a spore. Individual single cell filaments can fuse with other similar filaments and produce multicellular vegetative bodies which form the mycelium (or thallus) of the fungus.
Mushroom – The term “mushroom” describes the above ground, fleshy fruiting body of a fungus. Mushrooms are produced from mature mycelium when environmental conditions are suitable. Mushroom is the fungal part or stage that produces spores and is commonly eaten as nutritious food. Synonyms: fruit body, fruiting body, sporocarp.
Mycelium – “Mycelium” is a network of hyphae, the fine thread-like filaments that grow within and around their food source, e.g., woody debris, soils, grasses, other organic matter. Mycelium is considered the vegetative body of the fungus and has a different identity and chemical profile than “mushroom.”
Myceliated Grain or Mycelium Grain Biomass – “Myceliated Grain” or “Mycelium Grain Biomass” is produced by the same manufacturing process used to produce Grain Spawn, although the mycelia may incubate longer. Once the grain is fully colonized, the mycelium grain biomass is dried and ground into a powder and typically heat-treated before use in a finished food or dietary supplement. This process does not remove the grain.
Primordia – “Primordia” are tiny aggregations of hyphae composed of a dense hyphal mesh representing a stage of growth that initiates the formation of the fruiting body. At this stage, primordia lack the structure and chemical composition of the mushroom.
Spawn - “Spawn” is seed for mushroom cultivation. It is created by inoculating a live mycelium into a sterilized medium, often grain or sawdust. Spawn is planted by mixing it into a prepared food source called a “substrate.”
Spore - A “spore” is a microscopic reproductive cell that is produced on the gills or pores of a mature mushroom. The spore is the reproductive structure of a fungal organism. When a spore germinates, it produces an elongated germ-tube called a “hypha.”
Sources
- Snell, H. & Dick, E. A Glossary of Mycology. (2014). Harvard University Press: 2nd ed; ISBN-10: 0674435524; ISBN-13: 978-0674435520
- Chang T, Wasser S. (2017). The Cultivation and Environmental Impact of Mushrooms, Oxford Res Encyclopedia Environ. Sci. DOI: 10.1093/acrefore/9780199389414.013.231.