Microbiological quality of Çökelek cheeses offered for sale in Diyarbakir and compliance with the Turkish Food Codex

Abstract

This study was conducted to determine the microbiological quality of Çökelek cheese samples obtained from various retail points in Diyarbakır province and to evaluate the findings according to the Turkish Food Codex Microbiological Criteria Regulation. Within the scope of the study, 60 fresh Çökelek cheese samples were analyzed for total mesophilic aerobic bacteria (TMAB), coliform group bacteria, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and yeast and mold counts. As a result of microbiological analyses, TMAB counts ranged between 6.32 and 9.97 log cfu/g, yeast and mold counts between 3.68 and 7.91 log cfu/g, and coliform bacteria counts between 2.30 and 4.69 log cfu/g. Among pathogenic microorganisms, E. coli was detected at levels of 2.48–3.89 log cfu/g, while S. aureus counts ranged from 2.60 to 4.92 log cfu/g. L. monocytogenes was detected in 23.3% of the samples, with counts ranging from 1.48 to 3.67 log cfu/g in positive samples. E. coli and S. aureus were detected in 30.0% and 70.0% of the samples, respectively. In addition, positivity rates for coliform bacteria (>10³ cfu/g) and yeast and mold (>10⁴ cfu/g) were determined as 85.0% and 80.0%, respectively. The findings demonstrated serious non-compliance with the Turkish Food Codex microbiological criteria for E. coli, S. aureus, and L. monocytogenes, particularly in positive samples with counts exceeding the regulatory limits. These findings indicate inadequate hygienic conditions during the production, storage, and sale of Çökelek cheese marketed in Diyarbakır and demonstrate a significant public health risk.

Keywords

• Çökelek cheese
• Microbiological quality
• Turkish Food Codex
• Listeria monocytogenes
• Food hygiene

Ethical Statement

The authors declare that this study includes no experiments with human or animal subjects. Ethics committee approval is not required for this study.

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