The effect of pressure cooking on aflatoxin residues in polished rice was conducted to determine
reduction of aflatoxin and mutagenic potentials. Three rice lots consisting of naturally contaminated,
A. parasiticus-infested, and aflatoxin-spiked rice were steamed by ordinary and pressure cookers
after they were washed with water. They were chemically analyzed for aflatoxins using a silica solid
phase extraction tube and high-performance liquid chromatography (HPLC)-fluorescence detection
(FD), and the presence of aflatoxin residues was confirmed using HPLC-electrospray ionization
(ESI)-mass spectrometry (MS). An in vitro mutagenicity test with Salmonella typhimurium TA100
was employed to verify the results based on chemical analyses. The aflatoxin loss (78-88%) was
notable after pressure cooking, and the reduction of aflatoxin-induced mutagenic potential (68-78%)
was in good agreement with the HPLC results. It can be concluded that Koreans are safe from the
aflatoxin-related risk if a pressure cooker is employed for cooking rice. The average Korean daily
intake of aflatoxin through the consumption of staple rice would fall to 0.15 ng/kg bw/day, which
would not exceed the established tolerable daily intake (0.40 ng/kg bw/day).