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.