Effects of Monascus application on in vitro digestion and fermentation characteristics of fish protein

The aim of this study was to investigate the digestion and fermentation properties of fish protein fermented by Monascus. Semi-dried fish was fermented by applying Monascus purpureus Went M 3.439. Our results show that the Monascus fermentation of the fish protein enriched the free amino acids and achieved a relatively higher glutamate content than the control group. The Monascus treatment promoted the decomposition of the fish protein during in vitro digestion, reduced the ammonia and indole content and tended to increase the propionic acid content during in vitro fermentation. The Monascus treatment considerably changed the gut microbiota composition, and particularly increased the relative abundance of Parabacteroides in the in vitro fermentation model of human distal colon. Consumption of Monascus fermented fish protein could result in positive changes in fermentation metabolites and gut microbiota, which brings potential health benefits.