Abnormal Contamination of Roquefort Cheese in Egypt

Abo-Gharbia, M.M. and El-Sawi, N.M. 1999. Abnormal contamination of Roquefort cheese in Egypt. J. Appl. Anim. Res., 16: 65–74. Roquefort cheese samples of Egyptian and Danish origin were tested for contamination. Chemical analyses revealed that the Roquefort cheese samples were rich in metals. Na was generally high but K, Mn, Ca, Cu, Cd and Ni were detected in low concentrations. Lead was found in Egyptian source only. Fifty-one fungal species belonging to 17 genera were collected and identified from 25 samples of cheese on two isolation media. Three bacterial genera (Streptococcus, Pseudomonas and Staphylococcus) in addition to coliform were identified in variable degree of counts (6.8, 0.6, 219.5 and 2.50 colonies mg g1) and occurrence (17, 3, 19 and 13 samples/25 samples). Four biogenic amines were detected in Roquefort cheese. Histamine was the most dominant in Egyptian and Danish samples. Tryptamine, cadaverine and putrescine appeared in Egyptian source with variable degree of occurrence and concentration. But, tryptamine was only detected in two samples of Danish source. Ten ethyl acetate extracts of Egyptian cheese samples had toxicity to brine shrimp larvae. Based on TLC and UV spectrophotometric analyses, roquefortin, aflatoxin B1 and B1 were detected.