title: Effects of high-pressure processing on Toxoplasma gondii tissue cysts in ground pork.
abstract: Ingestion of Toxoplasma gondii tissue cysts can result in severe disease in immunocompromised individuals and pregnant women. Treatment of meat and meat products to eliminate viable T. gondii tissue cysts would provide a means to protect consumers. In this study, we examined the effects of high-pressure processing (HPP) on ground pork containing viable tissue cysts of the VEG strain of T. gondii. Ground pork containing tissue cysts was exposed to 400, 300, 200, 100, or 0 MPa treatment for 30, 60, or 90 sec in a commercial HPP unit. The HPP-treated ground pork was subjected to acid-pepsin digestion and bioassayed in mice. The results of the mouse bioassay revealed that none of the mice inoculated with tissue cysts exposed to 400 or 300 MPa became infected, whereas all mice inoculated with tissue cysts exposed to 200, 100, or 0 MPa became infected with T. gondii regardless of exposure time. Results indicate that HPP treatment of ground pork with 300 MPa of pressure will render tissue cysts of T. gondii nonviable and make pork safe for human consumption.
authors.affiliation: Department of Biomedical Science and Pathology, Virginia Tech, 1410 Prices Fork Road, Blacksburg, Virginia 24061, USA. lindsayd@vt.edu
authors.forename: David S
authors.initials: DS
authors.lastname: Lindsay
authors.forename: Marina V
authors.initials: MV
authors.lastname: Collins
authors.forename: Daniel
authors.initials: D
authors.lastname: Holliman
authors.forename: George J
authors.initials: GJ
authors.lastname: Flick
authors.forename: J P
authors.initials: JP
authors.lastname: Dubey
mesh_terms: D000399:Air Pressure; D000818:Animals; D005506:Food Contamination / Q000517:prevention & control*; D005511:Food Handling / Q000379:methods*; D008460:Meat / Q000469:parasitology*; D051379:Mice; D013552:Swine; D013553:Swine Diseases / Q000469:parasitology*; D014122:Toxoplasma / Q000502:physiology*; D014124:Toxoplasmosis, Animal / Q000469:parasitology*