A Survey of Raw Milk For Microbiological Quality and Typing of Foodborne Pathogens by MALDI-TOF MS

Abstract

This study was conducted in order to determine microbiological quality of raw cow milk samples sold in public markets and to investigate foodborne pathogens in Giresun. The samples were examined for  total mesophilic aerobic bacteria, total  psychrotroph aerobic bacteria, coliform, Enterobacteriaceae, Micrococcus/Staphylococcus, lactic acid bacteria, yeast and mold, Salmonella spp., Escherichia coli O157:H7, L. monocytogenes, Bacillus cereus, Campylobacter spp. according to Food and Drug Administration/Bacteriological Analytical Manual and International Organization for Standardization methods. Identification of the isolated pathogens was made with Matrix-assisted laser desorption,  ionization time of flight mass spectrometry. The mean values of microorganism colonies detected in raw cow milk samples were as follows: total mesophilic aerobic bacteria count 5.87 log cfu/ml in 93 samples; total  psychrotroph aerobic bacteria count 5.69 log cfu/ml in 95 samples; coliform count 4.85 log cfu/ml in 12 samples; Enterobacteriaceae count 4.84 log cfu/ml in 18 samples; Micrococcus/Staphylococcus count 5.17 log cfu/ml in 94 samples; lactic acid bacteria count 5.54 log cfu/ml in 97 samples, and yeast and mold 5.16 log cfu/ml in 73 samples. Listeria monocytogenes, Escherichia coli were found as 6 (6%) and 34 (34%) in 100 raw cow milk samples respectively. Salmonella spp., Campylobacter spp., Escherichia coli O157:H7 and Bacillus cereus were not detected. As a result; a statistically significant presence of bacteria threatening human health was detected in the raw cow milk samples examined. In order to resolve this problem, it is thought that further similar studies should be conducted on the basis of procuders, consumers and supervisory institutions.