The assessment of sanitary measures of Ras cheese was undertaken through microbiological evaluation of cheese and its processing environments in traditional manufacturing dairy plant in Alexandria Governorate. A total of 215 representative samples include received raw milk (25), cheese curd (25), fresh Ras cheese (25), three months aged Ras cheese (25), and six months aged Ras cheese (25). As well as swabs from cheese vat (15), stainless-steel cylindrical forms (15), stainless-steel tables (15) and hand workers (15) were taken. Also (15) samples of rennet and (15) samples of annatto (coloring agent) were collected . The trials were repeated 3 times from 3 different patches within 6 months to ensure the most contaminated points. Raw milk was heavily contaminated as the mean value of total bacterial count , Coliforms count , S. aureus count and total Yeast & Mould count were 1.11 x 107 ± 2.45 x 106 cfu/ml , 8.24 x 104 ± 1.68 x 104 cfu/ml , 7.77 x 102 ± 4.33 x 102 cfu/ml and 4.10 x 102 ± 2.0x102 cfu/ml, respectively. Meanwhile Slight decline of all these counts were observed in curd samples . Then the counts increases again in fresh cheese samples specially Coliforms and S. aureus counts as folow 1.88 x 103 ± 8.13 x 10 cfu/gm and 1.64 x 103 ± 3.66 x 102 cfu/gm, respectively. Three aged cheese samples revealed slight reduction in Coliforms and S. aureus counts as follow 1.44 x 102 ± 2.14 x 10 cfu/gm and 8.41 x 10 ± 1.80 x 10 cfu/gm, respectively . Meanwhile, 6 months aged cheese samples shows great reduction of Coliforms and S. aureus counts as follow .2 x 10 ± 0 cfu/gm and 2.66 x 10 ± 8.43 x 10 cfu/gm, respectively indicating the fact that the prolonged aging of Ras cheese increase the safety of the product . Samples of rennet, Cheese vat, stainless-steel cylindrical forms and stainless-steel tables showed high contamination with TBC and Coliforms while hand workers swabs were harbored high S. aureus and Coliforms counts. Results pose that the most reliable sources of contamination along Ras cheese manufacturing line were received raw milk, rennet, vats, forms, tables as well as hand workers. Preventive measures and GMP these could be applied to improve the hygienic quality of Ras cheese were fully discussed.
Key words: Ras cheese , Total Bacterial count, Total Coliforms count, Total S. aureus count and Total Yeast & Mould count
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