A Survey of Escherichia Coli, Enterococcus and Total Microbial Count of Packaged and Non-Packaged Fresh Vegetables in Tehran

Vegetables are one of the major components of food basket and consumption of them is on the rise. On the other hand, diseases and outbreaks caused by this group of foodstuffs have increasing trend. This study was performed to investigate the microbial contamination of vegetables used in south of Tehran.
Hundred fresh packaged and non packaged vegetable samples composed of 10 kinds, were examined based on the methods presented in Iran national standards. For each sample, enumeration of enterococcus and total microbial count was carried out by the pour plate technique in KF agar and plate count agar, respectively. Escherichia coli detection was also performed using lauryl sulfate broth, EC broth, peptone water and MacConkey agar mediums. Biochemical tests namely urea hydrolysis, motility, sulfide hydrogen (SH2) production, gas production and sugar fermentation were conducted as conformational tests of Escherichia coli.
All (100%) of mixed leafy vegetables, spinaches, peppers, kuku (Persian food) vegetables, wheat sprouts and mung been sprouts had contamination higher than acceptable limits. In the case of green onions, basils, kuku vegetables, mushrooms and broccolis, respectively 40, 60, 30, 90 and 30 % of the samples were in contravention with acceptable limits, in terms of at least one parameter.
Our results show that consumption of vegetables specially those used as raw, need more attention at washing point and need to use hygienic rules of health department and health care centers, at shopping and consumption steps.