Sulforaphane formation and bioaccessibility are more affected by steaming time than meal composition during in vitro digestion of broccoli

The main formation of SF and SFN occurred during in vitro chewing. The contents of GR, SF and SFN did not change after further digestion, as the irreversible inactivated myrosinase under gastric conditions caused no further GR hydrolysis. SF concentrations were up to 10 times higher in raw and 1 min steamed broccoli samples after digestion compared to longer-steamed broccoli. Protein or lipid addition had no influence on the formation and bioaccessibility of SF or SFN.