Survey on Traditional Kurdish Cheese Pathogenic Flora During Ripening Periods

Traditional raw milk cheese is one of the most consuming cheeses in the world. However, pathogenic bacteria that can be transmitted through the dairy products, including cheese, are important from public health point. There have been reported some outbreaks of infection associated with the consumption of cheese and the presence of pathogenic organisms in it. Kurdish cheese is a semi-firm, traditionally made in the East of Iran. It is manufactured from raw sheep or cow milk and kept in goat’s skin bags during ripening period. As a result Kurdish cheese is often more complex in different varieties of microorganisms, which whose organoleptic properties make it highly esteemed. The aim of this study was to investigate the cheese microbiological contamination during 1, 20, 40 and 60 days of ripening periods, in local condition. Total mesophilic bacteria count; yeast and mold, coliform, E.coli, staphylococcus aureus and salmonella were enumerated according to National Standards of Iran. According to our results, After 20 day of ripening the numbers of micro-organisms reach their maximum, coliforms and E.coli were the predominant groups. But, at the end of the ripening period, No coliforms and E.coli were detected in the cheese samples, confirming that these were not contaminated with undesirable flora. The total average Moulds and yeasts of 2 white cheese samples was 4. 105 cfu/ml at first day of production but after 20 days of ripening it increase sharply and after that decrease gradually in ending days. No Coagulase positive Staphylococcus was detected at the end of the ripening period. Salmonella was not detected in any samples examined. pH content of samples decreased slowly during ripening. According to our results, the presence of high counts of pathogenic flora in cheese samples in first days of production suggests inadequate hygiene practices during transport and manufacture of this traditional food. But the optimize time for consuming kurish cheese would be after passing ripening times (60 days) due to decrease in pH, undesirable flora and increase in desirable LAB counts.