Enhancing Microbial Food Safety by Risk Analysis

<p>NON-TECHNICAL SUMMARY: Foodborne illness is a significant public health concern, with an estimated 48 million cases of foodborne illness each year in the U.S. alone. In addition to health care costs, the presence of human pathogens in the food supply has a substantial economic effect on the food industry in the U.S. due to product recalls and loss of consumer confidence. Pathogens such as E. coli, Salmonella, and Listeria monocytogenes are responsible for the majority of severe foodborne illness. These pathogens are capable of surviving in a number of different food products, including fresh produce and low-moisture foods. A clearer understanding of how these pathogens are capable of surviving on foods during handling and processing will allow development of new control strategies to reduce pathogens in the food supply. To determine how bacterial pathogens are able to survive different stresses present on foods, we will expose them to different stresses and measure changes in gene expression and quantify the number of bacteria that survive. Changes in gene expression are one indication of how a bacterium is reacting to a stress in order to protect itself from further damage. In some cases, the genes induced by one stress can lead to increased resistance to a subsequent different stress. Using this information against the bacteria, such as combining stresses or processing steps in a different way, could lead to sensitization of the bacteria to the stress, making them easier to elminate from the food. </p>