In vitro protein digestibility of edible filamentous fungi compared to common food protein sources

Edible filamentous fungi, as a source of mycoprotein, is an emerging sustainable protein source as it can be cultivated on food-industry sidestreams, thus providing the food system with circularity. However, the digestibility of mycoprotein from different species of fungi is yet to be studied and compared to commonly consumed food proteins derived from muscle. Using the static INFOGEST in vitro gastrointestinal (GI) digestion protocol, but with less pancreatin than the recommended amount to omit high background from enzyme autolysis, this study investigated the protein degree of hydrolysis (DH%) and amino acid accessibility of five species of edible fungi in comparison with salmon fillet, chicken breast, beef tenderloin and casein. Three of the edible fungi species reached protein DH% between 58% ± 2.6% and 62% ± 5.6% during GI digestion compared to chicken, salmon, and beef reaching 62%–67% as well as casein at 55%. The amino acid accessibility of fungi (81%–92%), was comparable to that of salmon, chicken breast, and beef (90%–94%). This study thus indicated that edible fungi is a sustainable and nutritionally sound protein source.