Enteric virus detection and inactivation in model food systems
by Hirneisen, Kirsten, M.S., UNIVERSITY OF DELAWARE, 2008, 108 pages; 1460127

Abstract:

Foodborne illnesses caused by enteric viruses represent an underestimated sector of food safety. The high occurrence of gastroenteritis caused by viruses is likely due to their low infectious dose, possible low levels of contamination, stability in the environment and on foods as well as the difficulties they pose in culture and detection. This study aims to determine the effect of food components on viral inactivation by high pressure processing (HPP). As part of this work, virus sampling and detection in model foods by flow-through immunomagnetic capture was assessed. This method of viral detection used cationic beads for initial isolation followed by virus infectivity to determine the amount of live virus recovered instead of relying on molecular detection. The effect of recovery from differing food matrices was tested including a low pH solid, salsa, and a neutral pH liquid, milk. Recovery of virus from 3 representative families (Caliciviridae, Poxviridae, Picornoviridae ) were studied by varying eluting solutions (Hanks Balanced Salt Solution, H2O, a basic elution buffer (3% beef extract) or a 0.1N HCl solution) to determine the effect on infectivity. Results indicated that picornaviruses (HAV and AiV) were able to be recovered in both milk and salsa and pH may play a role in this recovery of virus from the food matrix. High pressure processing (HPP) is a novel technology that can inactivate foodborne pathogens, including viruses. Various components of food such as protein, fats and carbohydrates have the ability to protect viral inactivation by HPP. This study assessed the protective effects of various food components focusing on fats and proteins on viral inactivation by HPP in seafood salad using cod, shrimp, tuna and clams. HPP inactivation of viruses varied in seafood salad indicating the complex interactions that occur between the virus particles, food and the applied pressure. As demonstrated by this work, enhanced methods of virus detection in foods coupled with improved processing parameters aimed at viral inactivation may reduce the likelihood of viruses as a cause of foodborne illness.

 
AdviserKalmia E. Kniel
SchoolUNIVERSITY OF DELAWARE
SourceMAI/ 47-03, p. , Feb 2009
Source TypeThesis
SubjectsFood science
Publication Number1460127
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