Assessment of listeria monocytogenes, staphylococcus aureus and salmonella SPP. Contamination in dairy samples collected in Gia Lam and Ba Vi, Hanoi early 2019

Abstract

Milk and dairy products from dairy farms around Hanoi greatly contribute to the consumed milk quantity in Hanoi. The use of fresh milk or pasteurized milk becomes more and more popular in the daily life of local people. Milk and dairy products were widely sold in numerous stores, particularly in Xuan Mai, Ba Vi, Phu Dong and Gia Lam. However, there have not yet been any studies to assess the pathogenic bacterial contamination of these products. In our study, 49 samples including 23 raw milk samples, 12 pasteurized milk samples, and 14 yogurt samples were collected in order to examine the presence of food­born pathogenic bacteria such as Listeria monocytogenes, Staphylococcus aureus, Salmonella spp. using PCR method. This fast and accurate method works based on the specific amplification of tested bacterial DNA. The results showed that one of the samples may contain Staphylococcus aureus while another may be contaminated with Listeria monocytogenes. None of the samples was contaminated with Salmonella spp. The results were confirmed by gene sequencing.