Microbial quality of selected ready-to-eat vegetables from Iwo, Nigeria and effectiveness of rinse agents

Abstract

Consumption of fresh vegetables promote good health and is encouraged but possess a wide range of microbial contaminants and have been implicated in several foodborne disease outbreaks. Washing can reduce microbial load of pathogens thereby minimizing harm to consumers. The focus of this study was to assess the effectiveness of rinse agents (plain water, salt, vinegar and chlorine solutions), on the microbial content of ready- to- eat vegetable (cucumber, spinach and lettuce) samples using standard methods. Microbial load of unwashed vegetables ranged from (3.8 × 105 - 1.2 × 107 CFU/g); (1.2 × 106- 2.1 × 107 CFU/g); and (1.3 × 107 - 2.6 × 107 CFU/g) for total viable, enterobacteriacea and staphylococcal count respectively. There was 1-2 log reduction in the microbial load of vegetables after rinsing. Chlorine and vinegar solutions are more effective than plain water. Nine genera of bacteria were identified before rinsing including Staphylococcus, Pseudomonas, Bacillus and E. coli. However, after rinsing, 2 to 7 species were identified. Study concludes that ready to eat vegetables are contaminated with different bacteria genera of public health concern. Plain water was not effective enough for the reduction of microbial load therefore chlorine or vinegar rinse could be adopted.