Bacteriological assessment of some vegetables and ready-to-eat salads in Alexandria, Egypt

Fresh vegetables and ready-to-eat salads (RTES) are essential components of human diet. Despite their benefits, they remain a major public health concern, because they have been implicated in foodborne illness outbreaks in numerous countries.

The present study aimed to assess the bacteriological quality of some fresh vegetables and RTES in Alexandria, Egypt.

This cross-sectional study included 121 samples of vegetables and RTES that were randomly purchased from different markets, restaurants, and street vendors in three districts in Alexandria. All samples were subjected to heterotrophic plate count using pour plate method; detection and enumeration of total coliforms, fecal coliforms and Escherichia coli by multiple tube dilution method; and isolation and detection of Salmonella spp. using standard microbiological methods.

The aerobic colony count (ACC) for the 71 tested fresh vegetable samples ranged from 2.0 to 10.4 log CFU/g. Green pepper had the highest ACC mean value (8.4 log CFU/g), whereas lettuce showed the lowest ACC mean (5.1 log CFU/g). Fecal coliforms were detected in 90.1% of tested vegetable samples and 66% of the examined RTES samples. Of the 22 street-vended RTES samples, 18.2% were significantly unsatisfactory regarding E. coli. Salmonella spp. was not detected in any of the examined samples.

All examined samples were contaminated and yielded growth of aerobic mesophilic bacteria with varying densities. According to the Public Health Laboratories guidelines, only street-vended RTES samples yielded unsatisfactory levels of E. coli, which indicates the need for close supervision and regular inspection of hygienic practices and preparation methods of street-vended salads.