Mycelium as a natural food fortificant: production, micronutrient enrichment, processing, and application in functional foods.

The vegetative body of filamentous mushrooms, known as mycelium, has attracted significant interest as a nutrient-rich, sustainable food ingredient that can help address micronutrient deficiencies and protein malnutrition worldwide. In contrast to synthetic fortificants, mycelium is a natural fortificant that bioaccumulates minerals (iron, zinc, selenium, etc.) and vitamins (vitamin B12 and vitamin D2) during fermentation, thus becoming a promising clean-label ingredient and fortificant. This review focuses on the nutritional (both macronutrient and micronutrient) profile of mycelium, including protein composition, minerals, vitamins, bioactives, etc. It also discusses different methods, i.e., submerged, solid-state, and precision fermentation for producing mycelial biomass. This study also explores micronutrient enrichment methods, such as biofortification, UV-assisted vitamin D2 enhancement, and encapsulation for mineral delivery. It discusses the application of mycelium in various functional foods, including meat substitutes, baked goods, dairy alternatives, and beverages. Additionally, the discussion covers sustainability and the environmental impact of mycelium, current challenges to its commercial use, and future developments. Mycelium offers a scalable, eco-friendly, and physiologically adaptable solution to hidden hunger, protein deficiency, and the drawbacks of traditional synthetic food fortification.