Microbial risk assessment of dairy products from retail marketplaces in Basrah province, Iraq

Abstract

Background: Milk-borne bacteria cause degradation of milk products and constitute a significant risk to public health. Aim: The objectives of present study are to determine the microbiological quality of dairy products and to investigate pathogenic microorganisms. Methods: A total of 60 samples of raw milk, homemade cheese and yogurt were randomly selected from different retail marketplaces in Basrah. The bacteriological and biochemical tests were utilised to identify the pathogens in dairy samples, as well as the molecular technique was used as accurate diagnostic test. Results: The prevalence of contamination milk products with various isolates was estimated as 50% (95% Cl: 36.8-63.2). The mean of total bacteria count (TBC) for cheese was 7.29±2.70, raw milk 4.62±2.86, and yogurt 2.87±1.05, with significant p-value (P=0.001). The mean count of aerobic spore-forming (ASF) contaminated raw milk was analysed as 3.77±1.18 and less contamination detected in the yogurt samples with mean of ASF was estimated as 2.52±1.47 SD log 10 CFU/ml. A range of important microorganisms to human health were identified through employing the VITEK_2 system and sequencing 16S rDNA gene, including Staphylococcus aureus, Escherichia coli, Pseudomonas aerogenosa, and Bacillus cereus. Conclusion: The study indicates that there is a high level of bacterial contamination in the dairy products with different bacteria species, which is medically important. Therefore, food safety management must be implemented to reduce biological risk carried by dairy products and ensure healthy food for consumers.