Microbial contamination of soft cheese may originate from various sources such as contaminated equipment or from the workers themselves during cheese production. The study was aimed to characterize Bacillus cereus using culture-based and PCR techniques among 285 samples along Damietta and Kareish cheese producing line in a small cheese plant in Alexandria governorate including raw milk, cheese, whey, rennet, water, and swabs from all contacts surfaces. Overall of 10.90 % and 10 % among raw milk, cheese, whey, rennet, water, and swabs from all contacts surfaces were positive for Bacillus species in Damietta and Kareish cheese producing line. The incidence of Bacillus cereus in receiving raw milk, curd, whey, fresh cheese samples were 6.66, 13.33 and 13.33%, respectively for traditional Damietta cheese plant. Bacillus cereus is found in only 6.66 % in receiving raw milk, pasteurized milk and fresh cheese samples for traditional Kareish cheese plant. Hbl, Nhe and Cytk genes were detected in Bacillus cereus isolated from curd and Damietta cheese. Nhe gene was detected in Bacillus cereus isolated from raw milk, pasteurized milk and Kareish cheese While, Ces gene was detected only in Bacillus cereus isolated from fresh Kareish cheese samples. The prevalence of Eneterotoxigenic virulent B. cereus poses public health threats to consumers. HACCP should be implemented for all steps of manufacture in order to produce a safe and good quality dairy product.
Key words: Bacillus cereus, Damietta cheese, Kareish cheese, virulent genes,
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