CONTROL OF HEPATITIS A VIRUS AND ESCHERICHIA COLI O157:H7 IN GREEN ONIONS AND SPINACH

The microbial safety of fresh fruits and vegetables is of global concern. Several recent outbreaks of hepatitis A virus (HAV) associated with green onions and Escherichia coli O157:H7 with vegetables have heightened the concern with the safety of consumption of these foods. These outbreaks suggest data gaps exist at all levels from the farm to the consumer with respect to microbial safety of fresh and fresh-cut produce. Few or no studies have addressed the interaction of HAV and E. coli O157:H7 with growing spinach or green onion plants. At the post-harvest level, control measures for these two pathogens in spinach and green onion are either not available or not effective. In this proposed project, we intend to determine whether HAV and E. coli O157:H7 can localize at internal sites of spinach and green onions during growth through contact with contaminated irrigation water. At the post-harvest level, we would investigate the potential of using non-thermal processing technologies, high pressure and UV treatments, to destroy HAV and E. coli O157:H7 in green onions and spinach. We expect to obtain a better understanding of routes of introduction of HAV and E. coli O157:H7 into spinach and green onions at the pre-harvest level and develop control measures to reduce/eliminate HAV and E. coli O157:H7. Results obtained from this study will be used to develop recommended commercial practices to produce processors and grower/packers. This project will help to improve the safety of fresh and fresh-cut vegetables.