Abstract

: A total of thirty (n = 30) packaged pasteurized milk samples were collected from two factories in Khartoum (A) and White Nile (B) States, Sudan and investigated to determine their physical, chemical properties and bacterial quality. The results revealed that no significant differences in color, taste, flavor and consistency of the samples. Clot on boiling test revealed that no acidity on day 3 and 6 post production. However, on day 9, 40% (for 6 samples) from factory A and 20% (for 3 samples) from factory B were positive due to ineffective pasteurization. Titratable acidity test met the standards of Sudanese Standard and Metrology Organization (SSMO) in acidity degree for both factories (p>0.05). Phosphatase test revealed that only 6.7% of samples from factory A were positive. Total number of nonpathogenic bacteria test showed high significant differences (p<0.01). The presence of Escherichia coli at the rate of 6.7% in factory A and 60% in factory B indicates fecal contamination which demonstrated the hygiene procedures in milk preparation for both factories which should be taken consideration before it was contributed to consumers.

Keywords:

Milk pasteurization, milk quality control, Sudan,

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The authors have no competing interests.

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