Microbiological investigation of coliforms and Listeria contamination in traditional cheese from Babol City, Iran, during the fall 2020: Short report

BACKGROUND: Traditional cheese has a special place in the diet of the people. However, its contamination with pathogenic microorganisms can endanger human health and cause significant economic losses. This study aimed to determine the contamination of traditional cheese by coliforms and Listeria. METHODS: In this cross-sectional study in Babol City, Iran, 60 samples of traditional cheeses (Khiki, Tabrizi, and Lactic) were randomly collected in the Fall (October, November, and December) of 2020. To separate Listeria, Listeria selective enrichment broth and PALCAM Listeria selective agar were used. MacConkey agar was used for coliform detection. Frequency distribution table and one-way analysis of variance (ANOVA) with SPSS software were used for data analysis. RESULTS: Sixty-five percent of Khiki cheese, 67% of Lactic cheese, and 55% of Tabrizi cheese samples were contaminated with Listeria. Moreover, 35% of Khiki cheese, 28% of Lactic cheese, and 59% of Tabrizi cheese samples were contaminated with coliforms. A significant relationship between microbial contamination and the West region of the city was observed (P = 0.04). CONCLUSION: Contamination of cheese samples taken in this study with coliform and Listeria indicates the poor quality and hygienic condition of traditional cheeses offered in Babol City; therefore, the necessary measures should be taken to create appropriate conditions for hygiene.