Macedonian Veterinary Review (Jan 2012)
Assessment of the microbial parameters along the production phases at a dairy plant
Abstract
The main objective of this paper was to detect the prevalence of pathogenic bacteria (Listeria monocytogenes, Campylobacter spp., Salmonella spp., Staphylococcus aureus and Escherichia coli) in raw milk, to assess the hygiene parameters during the milk processing and to evaluate the safety of the fi nal dairy products using standard ISO methods. Staphylococcus aureus showed highest prevalence of the pathogen microorganisms (85%), followed by Escherichia coli (46%) and Listeria monocytogenes (9.8) in bulk tank milk samples. Campylobacter spp. and Salmonella spp. were not detected in any of the tested samples.The swab samples taken from employees and working surfaces, water samples and pasteurized milk samples detected inadequate sanitary procedures during the phase of milk processing. Analysis of the swabs from employees hands revealed 1 positive sample for enumeration for Enterobacteriaceae and 7 samples with higher total viable count that did not comply withthe legislative, while the analysis of the swabs from working surfaces detected 5 samples positive for Enterobacteriaceae and 4 samples with higher total viable count that did not comply with the same legislative. The analysis of the water samples detected 2 samples with higher total viable count on 22°C, 2 samples for total viable count on 37°C and 1 sample for coliform bacteria that did not comply with the national legislative. None of the samples showed presence of Pseudomonas aeruginosa, Escherichia coli, sulphite reducing clostridia and intestinal enterococci. The analysis ofthe pasteurized milk confi rmed 3 samples with presence of Enterobacteriacae, 1 sample for coagulase-positive staphylococci and 2 samples with high total viable count at 30°C that did not comply with the national legislative. The analysis of fermented milk products and cheese samples confirmed the need for immediate corective measures and subsequently, improved sanitation procedures. The testing detected 9 samples of fermented milk products for the Enterobacteriacae criteria and 1 sample for coagulase-positive staphylococci criteria that did not comply with the national legislative. The analysis of cheese identifi ed 4 samples for Escherichia coli and 2 samples for coagulase-positive staphylococci that did not meet the criteria given in the national legislative. The goal of the food safety system in the food production is to assure a safe and reliable product which will lead to consumer safety, satisfaction and future greater confi dence in the company products.
