Chapter 9 - Foodborne pathogenic bacteria in fresh-cut vegetables and fruits

Abstract

Fresh-cut-produce-associated foodborne outbreaks are a major public health concern worldwide. Recent foodborne outbreak statistics showed that there is an increasing trend in fresh-cut produce-linked outbreaks mostly associated with Salmonella and Escherichia coli O157:H7 as the causative agents. There are multiple sources of contamination for fresh produce during preharvest and harvest–postharvest stages of production. Both endophytic and epiphytic colonization have been reported for foodborne pathogenic bacteria in fresh produce. The endophytic colonization occurs through natural openings, damaged tissue, and chemotaxis. The mechanisms of attachment for epiphytic colonization mainly include curli, fimbriae, flagella, and biofilm formation. Once attached onto the injured parts of the tissue, pathogenic bacteria can grow to high numbers in fresh fruits and vegetables. The interaction of the bacterial cell with the damaged plant tissue can result in the upregulation of genes involved in attachment, virulence, and resistance to oxidative antimicrobial agents. This represents a major challenge for the fresh-cut industry, as oxidative sanitizers are mainly used for the sanitization of fresh-cut produce, especially leafy greens.