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Abstract One hundred random samples of UHT milk, Feta cheese, processed cheese and yoghurt (25 of each) were collected randomly in clean, dry and sterile containers, from student hostels in faculty of Veterinary Medicine, Alexandria University for evaluation chemical, keeping quality and microbiological status of UHT milk and other dairy products. The obtained results could be summarized in the following items. 1. UHT milk: The mean value of fat, protein, lactose, SNF and Ash were 2.04±0.09, 2.44±0.05, 3.53±0.04, 6.47±0.09 and 0.19±0.01, respectively. Mean value of acidity percent was 0.17±0.01 Mesophilic aerobic bacterial count and Staphylococcus aureus were detected in 56 and 16% with mean values of 2.85x103 ± 0.64×103 and 1.1x103±0.41×103 Cfu/ml, respectively. While Coliforms, Salmonellae and Shigella failed to be detected in examined samples of UHT milk. Egyptian Standard (2005) stated that fat and SNF content of UHT milk should not less than 3 and 8.5, respectively, there was 60 and 100% of examined UHT milk samples not conformed to these standards. In addition, Egyptian standard (2005) stated that acidity percent of UHT milk should not more than 0.17, there was 12 % of examined UHT milk exceeding this limits. 2. Yoghurt Mean value of acidity percent in examined yoghurt samples was 1.68± 0.024 with minimum and maximum values were (1.40) and (1.85). Psychrotrophic, Coliforms and Staphylococcus aureus were detected in examined yoghurt samples at level of 16, 8 and 8% with mean values of 8.5x103 ± 6.2×103, 9.5x102 ± 2.5×102 and 9.0x102 ± 1.0×102 Cfu/g, respectively. Salmonellae and Shigella failed to be detected in any examined yoghurt samples. Egyptian Standard (2005) stipulated that yoghurt must be free from Staphylococcus aureus and salmonella, there was 8 and 0% of examined yoghurt samples were exceeding these standards 3. Feta cheese: Mean values of acidity, moisture percent and sodium chloride content in examined feta cheese were 1.29± 0.046, 53.77± 0.31 and 2.81± 0.37, respectively. Mesophilic aerobic bacterial count, Psychrotrophic, Coliforms and Staphylococcus aureus were detected in examined feta cheese samples at level of 60, 48, 12 and 8% with mean values of 2.76x103 ± 0.82×103, 1.89x103 ± 0.41×103, 1.0x103 ± 0.28×103 and 8.0 x102 ± 0.2×102 Cfu/g, respectively. Salmonellae and Shigella failed to be detected in examined feta cheese sample. Egyptian Standard (2005) stipulated that feta cheese must be free from Staphylococcus aureus and coliforms not exceed 10 cells/gm there was 8 and 12% of examined feta cheese samples were found exceeding these standards. 4. Processed cheese: Mean values of acidity, moisture percent and sodium chloride content in examined processed cheese were 1.26± 0.04, 29.04± 0.45 and 1.95 ± 0.13, respectively. Mesophilic aerobic bacterial count, Psychrotrophic, Coliforms and Staphylococcus aureus were detected in examined processed cheese samples at level of 88, 52, 24 and 8% with mean values of 5.1x103 ±1.6×103, 1.58x103 ±0.37×103, 3.5x103±1.05×103 and 1.2x103±0.25×103 Cfu/g, respectively. Salmonella and Shigella failed to be detected in examined processed cheese. Egyptian Standard (2005) stipulated that processed cheese must be free from Staphylococcus aureus and coliforms not exceed 10 cells/gm there was 8 and 24% of examined processed cheese samples were found exceeding these standards. |