Survey For Detection and Determination of Aflatoxins M1 and B1 in local Milk and Certain Dairy Products by Thin Layer Chromatographic Method.

Abstract

90 different type of milk samples, 10 Yogurt Samples, 110 different type of cheese samples and 10 ice cream samples were collected randomly from Giza Governorate during the summer of 1998 – 1999, for detection and determination of Aflatoxins M1& B1 by using thin layer chromatographic method. Results revealed that the average range of Aflatoxin M1 in milk samples amounted from 0.144 to 0.378 ng/ml. About 20 % of cows and buffaloes milk samples contained form 0.378 to 0.342 ng/ml of AFM1, whereas about 10% of other milk samples were contaminated with 0.162, 0.288, 0.324, 0.234, 0.144 and 0.162 ng/ml for skim , Pasteurized , sterilized, UHT, powder, and baby milk, in the same order. Concentrations of AFM1 detected in cheese samples, furthermore, varied due to the type and age of cheese being examined. 20% of cheese samples were contaminated with AFM1 being 5.1, 3.2, 2.99, 2.099, and 2.34 ng/gm for fresh Domiati, aged Domiati, Processed and Karish cheese, respectively, whereas, 30% of the other types of cheese contained 5.88, 6.3 and 3.4 ng/gm for Roquefort, fresh Romi, and Cheddar cheese, respectively. The lowest concentration of AFM1, of 0.116 ng/gm was detected, however, in 10% of yogurt samples. Meanwhile, 20% of ice cream samples were found to be contaminated with 2.7 ng/ml, and 10% of Feta cheese samples contained 3.3 ng/gm. It could also be appeared from results that both of cream and spread cheese were found completely free from this Aflatoxin, the lowest content of Aflatoxin detected in all of the above examined samples was 0.116, 0.162, 0.162 and 0.216 (ppb) in yogurt, skim, baby milk and cream, respectively. On the other hand, results also indicated that all milk samples were free from Aflatoxin B1 except one sample of skim milk (out of 10) which gave positive result.