Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/28/2005
Publication Date: 7/1/2005
Citation: Kingsley, D.H., Guan, D., Hoover, D.G. 2005. Pressure inactivation of hepatitis a virus in strawberry puree and sliced green onions. Journal of Food Protection. 68:1748-1751.
Interpretive Summary: Hepatitis A outbreaks associated with produce occur every few years in the US. The most recent example involved green onions served in a restaurant in Pennsylvania resulting in approximately 1000 clinical cases of hepatitis A virus and 4 deaths. Thus, identification of virus-intervention strategies for produce are highly desirable. High pressure processing (HPP) is used commercially as a non-thermal pasteurization process that has superior retention of flavor, texture, and nutrient content of treated foods. Given the previous demonstration that HPP can inactivate hepatitis A virus (HAV) in oyster tissues, the feasibility of using HPP to eliminate HAV in strawberries and green onions was examined. We demonstrated inactivation of 10,000 plaque forming units of HAV mixed in strawberry puree and on the surface of green onions after HPP at 54,500 psi for 5 min at room temperature. While some damage was evident to the pressure-treated produce, this application has merit for HAV inactivation in processed foods.
Technical Abstract: Hepatitis A can be acquired by consumption of contaminated produce. To investigate the potential of high pressure processing (HPP) as an intervention strategy for virus in produce, strawberry puree and sliced green onions were inoculated with > 1,000,000 PFU of hepatitis A virus (HAV) and treated with pressures ranging from 225 to 375 MegaPascals (MPa) in 25-MPa increments at ambient temperature. Subsequent virus extraction and plaque assay determined that HAV was inactivated in strawberry puree and sliced green onions after a 5-min exposure to pressures of 375 MPa with log10 PFU reductions of 4.32 and 4.75, respectively. The HAV was equally sensitive in puree and onions at pressures > 350 MPa. For pressure treatments of < 325 MPa, the virus was more sensitive to pressure in strawberry puree than in sliced onions with log10 reductions of 1.2, 2.06, and 3.13 observed for strawberries and 0.28, 0.72, and 1.42 observed for onions after 5 min treatments at 250, 275 and 300 MPa respectively. Although HPP may cause some organoleptic alterations to strawberries and onions, results show HPP will inactivate HAV in these foods.