On farm contamination of horticultural products in the USA and strategies for decontamination

Foodborne illness due to consumption of fruits and vegetables appears to be increasing in the USA. Fruits and vegetables can become contaminated with pathogenic and spoilage microorganisms throughout the preharvest and postharvest systems. Wild and domestic animals, soil, feces, irrigation water and human handling are potential preharvest sources, while harvesting equipment, transport containers, rinse water, processing equipment and human handlers can cause postharvest contamination. Differences and variability in surface morphology and metabolic functions of produce provide a range of ecological niches. There is a need to distinguish between surface contamination and potential growth of pathogens within produce. Effective decontamination may be due to lack of penetration of treatments to cells at increasing depths, neutralisation of treatment, formation of biofilms, and/or increased resistance to sanitisers upon attachment. Greater understanding of contamination, and why most decontamination treatments fail, may lead to farm-to-table multi-hurdle strategies to enhance the safety of fresh horticultural products.