摘要 : Processed cheese has an excellent history of safety; however, it is difficult to completely eliminate fungi and bacterial growth, activity and toxin production that threaten consumer health. 120 processed cheese samples from Egypt... 展开 Processed cheese has an excellent history of safety; however, it is difficult to completely eliminate fungi and bacterial growth, activity and toxin production that threaten consumer health. 120 processed cheese samples from Egypt were analysed for determination of total fungi and yeast count, as well as identification of the isolated fungi. Toxicity and aflatoxin produced by the isolated <i>Aspergillus flavus</i> using thin layer chromatographic technique. <i>Bacillus</i> species and <i>Clostridium perfringens</i> counted as sporeforming organisms. Fungi and yeasts were present in 18 (15%) of processed cheese samples with a total count of 2.7x10⁴/g. <i>A. flavus</i> was the first prevalent species (55.6%) of the positive samples. Five (25%) out of 20 isolates of <i>A. flavus</i> produced mycotoxins; 3 were able to produce all types of aflatoxins. Mycotoxin producing isolates cause more than 50% mortality in <i>Artemia salina</i> larvae. Some aerobic and anaerobic sporeformers were isolated and counted. <i>B. cereus</i> was isolated from 17 (14.2%) of processed cheese samples with an average count of 7x10²/g. <i>B. macerans, B. licheniformis</i> and <i>B. megaterium</i> were detected in 8 (6.7%), 20 (16.7%) and 14 (11.7%) of samples, respectively. Moreover, <i>C. perfringens</i> was present in 16 (13.3%) of samples. Two important points must be regarded for safe production of processed cheese: the first are the measures to minimize the presence of spores. The second is prevention of spore germination and vegetative proliferation by adequate cooling during all steps of production until distribution to consumers. 收起