What is the protein made by fungus?
The protein made by fungus is most commonly referred to as mycoprotein. This innovative, sustainably produced food ingredient is derived from the mycelium, which are the root-like, filamentous cells of a fungus. Unlike traditional mushrooms, which are the fruiting bodies of fungi, mycoprotein is cultivated using specific strains of microfungi in large bioreactors through a process called fermentation. This technology has created a versatile protein alternative with a unique texture that can mimic meat.
How mycoprotein is produced
Commercial mycoprotein production relies on advanced fermentation techniques. One of the most well-known examples uses the microfungus species Fusarium venenatum. The process involves several key stages:
- Fermentation: The selected fungal strain is cultivated in large, sterile vats known as bioreactors. A nutrient-rich liquid medium containing a carbon source (such as glucose) and a nitrogen source (such as ammonia) is fed into the bioreactor to encourage rapid fungal growth.
- Continuous Growth: The fermentation is a continuous process, allowing for the consistent production of fungal biomass. Oxygen, temperature, and pH levels are carefully controlled to optimize growth conditions.
- Heat Treatment: After harvesting, the fungal biomass undergoes a heat treatment to reduce its ribonucleic acid (RNA) content to safe levels for human consumption. High levels of RNA can increase uric acid in the bloodstream, potentially leading to gout.
- Processing: The treated mycoprotein is then dewatered, chilled, and processed into various food products. The natural fibrous nature of the mycelium allows it to be shaped and textured to resemble meat.
Nutritional and health benefits of mycoprotein
Mycoprotein stands out as a nutritious and beneficial food source. It offers several key health advantages, distinguishing it from both animal and other plant-based proteins.
Complete and high-quality protein
While many plant-based proteins are incomplete, mycoprotein from certain strains contains all nine essential amino acids that the human body cannot produce on its own. This makes it a complete, high-quality protein source comparable to animal proteins. Its Protein Digestibility-Corrected Amino Acid Score (PDCAAS) is exceptionally high, indicating its excellent nutritional value and bioavailability.
Rich in dietary fiber
A notable feature of mycoprotein is its high fiber content, which is significantly higher than most animal proteins. The fiber comes from the fungal cell walls, which are composed of chitin and beta-glucans. This fibrous matrix is largely insoluble and contributes positively to gut health and satiety.
Supports muscle protein synthesis
Studies have shown that mycoprotein is effective at stimulating muscle protein synthesis, particularly when combined with exercise. The anabolic effect on muscles is comparable to, or in some cases even greater than, that of animal proteins like milk protein. This makes it a valuable option for athletes and those seeking to maintain muscle mass.
Mycoprotein vs. Traditional Protein Sources
| Feature | Mycoprotein | Chicken | Beef |
|---|---|---|---|
| Protein Content (g/100g) | ~11g (fresh) | ~28.4g (cooked breast) | ~21.8g (cooked mince) |
| Dietary Fiber (g/100g) | ~6g (fresh) | 0g | 0g |
| Saturated Fat | Low | Variable, higher than mycoprotein | High |
| Cholesterol | None | Variable | Present |
| Land Use | Low (uses bioreactors) | High (requires land for livestock and feed crops) | Very High |
| Water Use | Low | Higher than mycoprotein | Very High |
| Environmental Impact | Low carbon footprint | High (GHG emissions) | Very High (GHG emissions) |
Broader applications and future outlook
Beyond its use in popular consumer products like Quorn™, fungal protein has numerous other applications. The versatility of mycoprotein and the efficiency of fermentation offer exciting possibilities for future food security and sustainability. Research and development continue to focus on optimizing production, exploring new fungal strains, and utilizing agricultural waste streams as substrates.
Feed for animals
Mycoprotein is also gaining traction as a sustainable and nutritious feed ingredient for livestock, poultry, and fish. It serves as a potent replacement for more resource-intensive feeds like fishmeal and soy protein.
Other functional proteins
In addition to mycoprotein, fungi are industrial workhorses that produce a variety of other valuable proteins and enzymes for different applications. These include industrial enzymes for biomass degradation and antimicrobials for pharmaceutical uses. For more information on fungal biotechnology, you can explore academic resources like this review on Fungal Cell Factories from the National Institutes of Health.
Conclusion
The protein made by fungus, primarily known as mycoprotein, is a powerful and increasingly popular alternative to animal-based proteins. Produced through efficient fermentation of fungal mycelium, it offers a complete amino acid profile, high dietary fiber, and a significantly lower environmental footprint than traditional livestock farming. As consumers and industries alike seek more sustainable food options, mycoprotein is poised to play a crucial role in shaping a more sustainable food future, proving that the kingdom of fungi holds a key to addressing global protein needs.
Challenges and Future Outlook
While fungal proteins offer significant promise, some challenges remain. The high initial capital cost of bioreactor facilities and the need for specific downstream processing, such as RNA reduction, can be limiting factors. Consumer acceptance is also a critical hurdle, as many still have misconceptions about fungi-based food. However, as technology advances and production scales up, these challenges are expected to lessen, paving the way for wider adoption of mycoprotein as a cornerstone of sustainable nutrition.
How the different types of proteins are produced from fungus
Fungi can be grown to produce various proteins through several methods:
- Mycoprotein (Filamentous Fungi): Cultivated through continuous submerged fermentation in large bioreactors, where specific strains like Fusarium venenatum grow as a fibrous mycelial network. The biomass is harvested, heat-treated, and processed into meat alternatives.
- Single-Cell Protein (Yeast): Yeasts like Saccharomyces cerevisiae are grown in liquid cultures, and their biomass is harvested as a protein supplement for both human and animal feed.
- Functional Proteins and Enzymes: Filamentous fungi are engineered to secrete specific enzymes (e.g., cellulases) or peptides (e.g., hydrophobins) for industrial, food, or pharmaceutical applications.
- Mushroom Proteins (Fruiting Bodies): Edible mushrooms contain proteins, but typically in lower concentrations by weight than cultured mycelium. They are a source of complete protein when dried.
By leveraging these diverse production methods, the fungal kingdom can supply a wide range of protein products to meet different demands across various industries.
