Changes in concentration of pesticide residues in potatoes during washing and home preparation

Monitoring of pesticide residues in potato tubers and their prepared produc ts ( "pommes frites" and chips) was undertaken. Experiments were carried ou t to determine changes in concentration due to the washing, peeling and coo king process (blanching and frying) to assess the stability of pesticides i n potatoes and their products. Pesticide residues were quantified by using gas chromatography. Results show that malathion, HCB, lindane and p,p-DDD w ere predominant in potatoes and their products. The highest mean was detect ed in potatoes, followed by pommes frites, while the lowest mean was record ed in chips. On the other hand, potato skin samples were found to contain t he highest levels of DDT and its derivatives, lindane and HCB. Peeling was necessary to remove the greatest amount of pesticides in the skin. Washing with water and/or other solutions as well as the cooking process (blanching and frying) helped to eliminate most of the pesticide residues from the po tato tubers. (C) 2001 Elsevier Science Ltd. All rights reserved.