FATE OF THIABENDAZOLE AND CHLORPROPHAM RESIDUES IN EXTRUDED POTATO PEELS

Potato peels from potato processing facilities have potential as a foo d ingredient, but the possibility of contamination with post-harvest p esticides may limit their usage as a source of dietary fiber. Peels pr oduced by steam peeling were twin-screw extruded in an attempt to redu ce the concentrations of two common chemicals applied to tubers in sto rage prior to processing. Extruded and nonextruded peels were analyzed for the fungicide thiabendazole and the sprout inhibitor chlorpropham (CIPC) by high-performance liquid chromatography. Two barrel temperat ures (104 and 143 degrees C) and three feed moistures (31, 33.5, 36%, dry basis) were studied. Peels contained 86.56 ppm thiabendazole and 3 3.12 ppm CIPC (dry basis) prior to extrusion. Extrusion cooking under these conditions did not significantly destroy either thiabendazole or chlorpropham.