ABSTRACT
Vegetables have been associated with outbreaks of foodborne disease in many countries. Organisms involved in these diseases include bacteria, viruses, and parasites. These outbreaks vary in size from a few affected persons to many thousands. Contamination of vegetables may take place at all stages during pre-and postharvest procedures. Cultivation and operation or preparation of vegetables is responsible for this contamination. Unsafe water used for rinsing the vegetables and sprinkling to keep them fresh is also a source of contamination. Other possible sources of microorganisms include soil, feces (human and animal origin), water (irrigation, cleaning), ice, animals (including insects and birds), handling of the product, harvesting and processing equipment, and transport (Johannessen et al., 2002). Microorganisms, normally present on the surface of raw vegetables, may consist of chance contaminants from the soil or dust. These include bacteria or fungi that have grown and colonized by utilizing nutrients exuded from plant tissues. Among the groups of bacteria commonly found on plant vegetation are mainly coliforms or precisely fecal coliforms, such as Klebsiella and Enterobacter. Microorganisms capable of causing human illness and others whose foodborne disease potential is uncertain, include Aeromonas hydrophila, Citrobacter freundii, Enterobacter cloacae, and Klebsiella sp. and these have been isolated in lettuce and salad vegetables. Plate count of aerobic mesophilic microorganisms found in food is one of the microbiological indicators for food quality (Aycicek et al., 2006). These organisms reect the exposure of the sample
4.1 Introduction ............................................................................................................................ 53 4.2 Taxonomy of Spoilage Microorganisms in Vegetables ..........................................................54
