Examination of Pathogenic Bacteria in Some Cake Samples
Thirty cake samples of twelve different companies were collected from Damietta and Dakahlia governorates in September and October 2012. All samples were in production date except one (A4) was expired. Thehigh contamination of examined cakes with mesophilic bacteria were found in A4 sample (286.76×103cfu/g) while the lowest value was found with B22 sample (0.12×103cfu/g). Samples of C11 (21.30×103) and A5 (0.07×103) cfu/g were the highest and the lowest values of thermophilic bacteria, respectively. Staphylococci presented in all examined cake samples except seven samples. The highest value was 3.50 ×103cfu/g in C13 sample followed by 2.90×103cfu/g in A14 sample. Aeromonas spp. was presented in all examined cake except A4 sample. The highly contaminated samples with Aeromonas spp. in case of A5 being 2.73×103cfu/g. The pathogenic enteric bacilli were found in all examined cake samples except sixteen which gave negative results. Results in positive samples were between 0.02×103 to 0.23×103cfu/gin D28 and C13, respectively. Eleven samples gave a negative results and nineteen were positive for coliform bacteria. Seven of cake sample gave negative results of Bacillus cereus while other samples, gave positive results ranged between 0.02×103 and 1.54×103cfu/g in C21 and D9, respectively. Twenty examined samples have not Vibrio spp. Results proved that C12 was the highest count being 2.92×103cfu/g. All samples were not in conformity with the Egyptian Organization for Standardization and Quality of cake (ES: 4037/2005). Forty-two bacterial isolates were obtained and identified according to the microscopic and biochemical examination. Obtainedbacterial isolates were identified as Bacillus cereus, Bacillus sublilis, Aeromonas spp., Pseudomonas spp., Echerichia spp., Salmonella spp., Shigella spp., Vibrio spp., Micrococcus spp. and Staphylococcus aureus.