Bacteria in milk have the ability to adhere and aggregates on stainless steel surface, resulting in biofilm formation in milk processing environment lead to increased opportunity for microbial contamination of the processed dairy products by spoilage and pathogenic microorganisms. So, to detect the biofilm problem in processed cheese factory a total of 130 swabs were collected from the surface of equipment used in manufacture of processed cheese along the processing line after cleaning and sanitization ((mixing tank, cold storage tank, pre heating (head A, B),hot storage ,UHT- sterilization(head A, B), flash tank , filter , creaming and hoopers ( Hooper 1,2,3) 10 samples from each from a manufacture plant in Alexandria Governorate. The samples were examined for aerobic mesophilic bacterial count, Coliforms, Staphylococcus aureus, Bacillus cereus and Clostridium perferingens. Bacillus and Clostridium species were failed to be detected in all examined samples. The most contaminated points with mesophilic aerobic bacteria were cold storage tank followed by Hooper (1) and flash tank. While, the highest contamination points with Coliforms were hooper (1) followed by cold storage tank and pre-heat head B. and finely, The highest contamination point with S. aureus were pre-heat head A followed by mixing tank and Hooper (2).
It is concluded that the good designing of food processing equipment and the selection of effective sanitation program with the rational running of processing line and frequent sanitation in short intervals are considered as solutions for lowering the incidence and minimizing the levels of biofilm formation.