EFFECT OF RAS CHEESE MANUFACTURING ON THE STABILITY OF DDT AND ITS METABOLITES

Residue levels of DDT were analyzed in 25 samples of liquid milk as we ll as 25 samples of Ras cheese collected from different regions in Gre at Cairo Governorates. Levels of DDT and its metabolites in liquid mil k samples were higher than those in Ras cheese. The detected levels of pesticides in milk and cheese were lower than the maximum acceptable limits (MAL(s)) recommended by FAO/WHO (1993). The reduction levels of total DDT in Ras cheese made from contaminated milk with different le vels of DDT (0.1, 1.0 and 10.0 mg/kg fat) were 40.6, 33.9 and 25.5%, r espectively, at the end of storage period. The isolated Ras cheese mic roorganisms reduced the total DDT residues by 10.8, 11.8 and 4.8% for Streptococci, lactobacilli and yeasts, respectively, at the end of inc ubation period. (C) 1997 Published by Elsevier Science Ltd. All rights reserved.