Influence of overcooking on in vitro fecal fermentation of foods

Areas of char or overcooking commonly appear in foods people consume. It has been reported that overcooked food is harmful to human health. However, little research exists on the effect of overcooking on gut microbial fermentation. Standard and overcooked beef and bread samples were subjected to in vitro digestion and fermentation using the fecal microbiota from eight healthy subjects. Overcooking decreased acetate, propionate, iso-butyrate, iso-valerate and ammonia production by the gut microbiota during fermentation of the beef sample, and decreased propionate and ammonia production during fermentation of the bread sample. Overcooking resulted in reductions in many Pseudomonadota and favored several Bacillota, especially Ruminococcaceae and Oscillospiraceae, which contain butyrate producers. Overall, overcooking reduced fermentation of proteins.