In vitro protein digestibility and colonic fermentation of mycoprotein-based meat analogues

The rapid growth of meat analogue products highlights the need to evaluate not only protein content but also protein quality, digestibility and colonic fermentability. Mycoprotein is a protein-rich fungal biomass with a favourable amino acid (AA) profile; however, limited data are available on the nutritional quality of mycoprotein-based meat analogues. This study compared protein digestibility, AA bio-accessibility and colonic fermentability of four mycoprotein-based meat analogues, their corresponding animal-derived meat counterparts, and mycoprotein biomass alone. Food products were subjected to a standardised in vitro digestion to determine in vitro Total protein Digestibility (ivTD) and in vitro Digestible Indispensable Amino Acid Scores (ivDIAAS). Further, digesta were assessed by in vitro batch colonic fermentation under proximal and distal conditions to evaluate microbial fermentation activity and short-chain fatty acid (SCFA) production. ABUNDA® mycoprotein biomass exhibited a balanced AA profile and high in vitro protein bio-accessibility. Mycoprotein-based meat analogues displayed slightly lower ivDIAAS values than their animal-derived counterparts, with only fish- and burger-type analogues failing to meet FAO protein intake requirements for both children and adults. Colonic fermentation of mycoprotein-based meat analogues resulted in higher overall SCFA production compared with meat counterparts, but this effect was observed only after 48h under distal colon conditions. Except for the fish-flake analogue, which showed higher butyric and propionic acid production, no major differences were detected in individual SCFA profiles between mycoprotein-based products and meat counterparts. Overall, these findings indicate that mycoprotein-based meat analogues can contribute to a balanced protein and fibre intake and represent a nutritionally relevant alternative to conventional meat products.