CHEMICAL AND MICROBIOLOGICAL EVALUATION OF MARKET RAS CHEESE

Twenty five samples of market Ras cheese were randomly collected and examined for chemical composition and microbiological quality. The average percentages of acidity, moisture, fat/DM and salt/DM were 2.22, 23. 16, 49.01 and 5.84, respectively. The averages of total - colony, coliforms, Staphylococci, aerobic spore-forming and anaerobic spore-forming counts per gram were 1.7x10°, 1.2x10', 2. 4x10*, 2x10* and 0.98 in order. Coliforms were detected in 60% of the examined samples and were identified as Escherichia coli (32%), Enterobacter aerogenes (12%), Enterobacter cloaca (8%), Citrobacter freundii (4%) and Hafnia alvei (4%). Staphylococci were detected in all of the examined samples and 20% of them were identified as Staphylococcus aureus. Aerobic spore forming and anaerobic spore-forming were detected in 100% and 60% of the examined samples respectively. Ras cheese samples were highly contaminated with total yeast and moulds with and average of 9. 8x10°/g.