Submitted to: International Association for Food Protection
Publication Type: Abstract Only
Publication Acceptance Date: 3/21/2007
Publication Date: 7/11/2007
Citation: Sharma, M., Kniel, K.E., Shearer, A., Solomon, M.B., Hoover, D. 2007. Comparison of hydrostatic and hydrodynamic pressure to inactivate foodborne viruses [abstract]. International Association for Food Protection Program and Abstract Book. p. 238. Interpretive Summary:
Technical Abstract: Viruses cause the majority of cases of foodborne illness in the United States. The lack of culturability of some foodborne viruses requires the use of alternate models, like non-pathogenic surrogates or bacteriophage, for inactivation studies. High pressure technology is currently being implemented in deli meat processing and may be an effective method to inactivate viruses in foods. The effect of high hydrostatic pressure (HHP) and hydrodynamic pressure (HDP), in combination with chemical treatments, was evaluated for inactivation of foodborne viruses, non-pathogenic surrogates, and bacteriophage in a pork sausage product. One-inch pieces of pork sausage were dipped in 2 percent lactoferrin, 100 mM EDTA, or water, and then inoculated with either 50 µl of feline caliclvirus (FCV), hepatitis A virus (HAV) or bacteriophage (MS2, phi 174, or T4) and dried. Each piece was packaged individually and subjected to pressure by either HDP at 10 deg C, HHP (500 MPa, 5 min, 4 deg C), or untreated. Viruses or bacteriophage were recovered by vortexing and assayed by TCID50 using cell culture or plaque assay with E. coli as a host strain. An average of 3.2 and 0.8 log HAV and 2.1 and 1.0 log FCV was inactivated by HHP and HDP, respectively. There was no significant difference in virus inactivation based on dipping in lactoferrin, EDTA, or water. There were no differences in inactivation of bacteriophage due to pressure treatments. HHP reduced phi 174 by 1.9 and 1.0 log PFU/g sausage after dipping in water and lactoferrin, respectively. No other combination of pressure and chemical treatments reduced bacteriophage titers by more than 1 log PFU/g sausage. This study is the first to directly compare the inactivation of viruses and bacteriophage by two pressure processes (HHP and HDP). Inoculation of viruses and bacteriophage on a meat product may have protected them from higher levels of inactivation by pressure treatments.