Mycelium biomass is the mass of organic matter from the vegetative part of a fungus. This network, similar to a plant’s root system, is cultivated and harvested for various uses. The final product is a combination of the mycelium and the fermented substrate it was grown on, creating a sustainable resource for several industries.
Understanding Mycelium
Mycelium is the branching, thread-like structure of a fungus, growing within soil or other substrates. This network is composed of fine filaments known as hyphae, which form an expansive web that is the main body of the fungus. Through this network, the fungus secretes enzymes to break down complex organic matter, absorbing the resulting nutrients from its environment.
In natural ecosystems, mycelium is a primary agent of decomposition, breaking down dead plant material and returning nutrients to the soil. Many plants also form symbiotic relationships with mycelium, known as mycorrhiza. In this partnership, the mycelial network extends the plant’s root system to increase water and nutrient absorption, while the fungus receives carbohydrates from the plant. Some networks can grow to be enormous, connecting different plants within an ecosystem.
Producing Mycelium Biomass
Producing mycelium biomass involves controlled cultivation through fermentation, where specific fungal species are grown on a substrate. Common substrates include agricultural waste products like sawdust, corn cobs, and straw, or grains like organic brown rice. Using these low-value byproducts makes the process resourceful and cost-effective.
Two primary methods are used for this cultivation: solid-state fermentation (SSF) and submerged fermentation (SF). In solid-state fermentation, the mycelium grows on a solid substrate with a low water content, which more closely resembles its natural habitat. This method is often used to produce fungal spores or specific enzymes.
Submerged fermentation involves growing the mycelium in a liquid nutrient medium within large tanks called bioreactors. This technique allows for precise control over environmental conditions and can lead to the rapid production of mycelial biomass. After the fermentation cycle is complete, the resulting mass of mycelium and digested substrate is harvested, dried, and powdered.
Diverse Uses of Mycelium Biomass
The versatility of mycelium biomass has led to its application across a wide range of industries, from food to fashion. Its fibrous structure and ability to bind organic materials together make it a highly adaptable resource.
In the food industry, mycelium biomass is used to create meat alternatives. The network of hyphae provides a texture that mimics muscle fibers, resulting in products with a meat-like chew and appearance. These food products are rich in protein and fiber. Companies are developing items from mycelium-based bacon to chicken breasts, offering a new category of plant-based protein.
Mycelium is also transformed into sustainable materials. It can be grown into specific shapes using molds, and once dried, it becomes a lightweight and durable material. This has led to eco-friendly packaging that can replace polystyrene and insulation panels for construction. In fashion, mycelium is processed to create a flexible and strong leather alternative.
The biological properties of mycelium allow for environmental applications. The same enzymes fungi use to break down organic matter can also degrade complex pollutants. This process, known as mycoremediation, uses mycelium to clean up contaminated soil and water. Fungi can break down hazardous substances, including pesticides, petroleum hydrocarbons, and heavy metals.
Ecological Impact and Sustainability
The use of mycelium biomass aligns with the principles of a circular economy. Its production relies on upcycling agricultural and forestry residues that would otherwise be considered waste, turning them into valuable products. This process reduces the burden on landfills and lowers the emissions associated with organic decomposition, contributing to a more resourceful industrial cycle.
Mycelium-based products have a lower environmental footprint than many conventional materials. Mycelium leather requires less water and land than animal leather and avoids the chemicals used in tanning. Mycelium composites for construction are lightweight insulators, reducing energy for transport and building climate control. Life cycle assessments show that some production models allow mycelium to act as a carbon sink.
At the end of their life, products made from mycelium biomass are biodegradable and compostable, unlike plastics that persist in the environment. The ability to return to the earth is a significant advantage. However, overall sustainability depends on factors like the energy sources and substrates used in cultivation.