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This study was undertaken to investigate the removal efficiency of heavy metals (Cd, Pb) in rice and wheat flour by cooking and processing. After four times washing of rice grains with water, the removal ratios of cadmium and lead from artificially-contaminated samples were 39.2% and 34.9%, respectively. In cooking of rice grains washed three-times with water, the residue levels of cadmium and lead decreased to 85.7%, 83.0% in electric rice cooker and 74.5%, 72.6% in pressure rice cooker, respectively. No significant difference was observed in the removal of the metals between naturally-contaminated and artificially-contaminated rice samples, and between the electric and pressure rice cookers. In baking of artificially-contaminated wheat flour into cookie and loaf bread, the removal ratios of cadmium and lead were negligible as expected. When knifecut noodle was made from artificially-contaminated wheat our and boiled in water, 75% of the metals were found in the noodle solids and only 25% of them were removed into the broth.
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