Removal of dicofol (Kelthane) residues from apple pomace.

Abstract

Chemical and physical decontamination procedures for dicofol [1,1′-bis(p-chlorophenyl)-2,2,2-trichloroethanol; Kelthane®], as applied to apples under controlled laboratory conditions, were studied on Red Delicious apple pomace (stems, cores, seeds, and peelings). Oven heating the contaminated pomace at 100°C for 24 hours, with and without excess moisture, removes 59.0% to 81.7% of the total dicofol residues. If the pomace is mixed with dry powdered alkali and heated, the residues are reduced 85.5% to 94.1%. If the pomace is mixed with dry powdered alkali and excess moisture, and heated, the total residues are reduced 98.7% to 99.1%. Vapor washing the pomace with water reduces the dicofol residues from 31.0% to 51.6%. Vapor washing the pomace with isopropanol reduces the dicofol by 65.6%. Cool-air drying, sunlight drying, ultraviolet light drying, and hot-air drying further reduces the total dicofol levels by 43.3%, 30.7%, 24.2%, and 40.6%, respectively, for the water-vapor-washed pomace, and 68.0%, 71.0%, 83.2%, and 94.0%, respectively, on the isopropanol-vapor-washed pomace. Dicofol residues can be effectively reduced on apple pomace by the above physical and chemical decontamination procedures. The decontaminated pomace can be utilized as a valuable feed by-product from apples.