Mycelium of mushroom-producing fungi as high-quality protein source

To achieve a more sustainable food system, reducing reliance on animal-based proteins is essential. Mycoprotein from mushroom-producing fungi (Basidiomycota) presents a promising yet underexplored alternative. Basidiomycetous mycelium combines the high protein quality of fungi with the sensory qualities of mushrooms. This study compares the mycelium of commercially cultivated and edible basidiomycetes to their fruiting bodies (FBs) and to mycelium of Rhizopus microsporus var. oligosporus (tempeh fungus). Nutritional quality was assessed via protein content and protein digestibility corrected amino acid score (PDCAAS), while sensory potential was analysed through equivalent umami concentration (EUC) and pyrazine levels. High-performing species surpassed the EUC of R. microsporus and FBs, reaching 301.0 g MSG-eq/100 g DW. Basidiomycetous mycelia exhibited superior protein quality (untruncated PDCAAS up to 1.20) and utilizable protein content (33.2 g/100 g DW), qualifying as an “Excellent protein source” according to the FAO. Given the phylogenetic diversity of basidiomycetes, this study highlights the untapped potential of its mycelium as a high-quality protein source.