incidence levels of enteric pathogens and microbial quality of raw vegetables in mashhad, iran

we investigated the microbiological quality of raw vegetables in mashhad, iran. in order to document the incidence of indicator and pathogenic microorganisms in this area. ninety eghit raw vegetable samples collected during 7 months were analyzed. all samples were examined for the presence of aerobic mesophilic bacteria, coliforms, enterobacteriaceae, escherichia coli, escherichia coli o157:h7, salmonella spp., staphylococcus aureus, yeast and mould. our data showed that the incidence levels of aerobic mesophilic bacteria was less than 107 cfu/g on 83% raw vegetables and 100% of raw vegetables were contained entrobacteriace and total coliforms, and their range varied from 1 log to 6 log cfu/g. the mean counts of lactic acid bacteria and yeasts and moulds were 4.1 log cfu/g and 4.5 log cfu/g, respectively, and the incidence levels of yeasts and moulds in 83% of raw vegetables was less than 5 log cfu/g. our results were similar with other studies that determined microbial levels on raw vegetables. 12.7% of samples raw vegetables contained e.coli, but only 4.1% were higher than ≥ 2 log cfu/g. the incidence levels for e.coli o157:h7 and salmonella on raw vegetables were 6% and 12.7% respectively. 94.9% of raw vegetables were contaminated with s. aureus and 7.8% of them were coagulase positive.