It has been reported that LMW brown MRPs isolated from dry-heated glucose–glycine systems (125 °C, 2 h) (Glosl et al., 2004), and HMW brown MRPs from aqueous sugar-lysine model systems (121 °C, 1 h, pH 9.0) (Jing & Kitts, 2000) have genotoxic and cytotoxic effects on cells in high doses. Bread crust and coffee melanoidins were also shown to impair the viability of lung epithelial H358 cells in high doses