High-pressure processing (HPP) of raw and dry-cured ham from experimentally infected pigs as a potential tool for the risk control of Toxoplasma gondii

摘要

Raw and dry-cured meats have been identified as a potential source of Toxoplasma gondii infection for humans. The present study evaluated the efficacy of an alternative non-thermal food-processing treatment, high hydrostatic pressure, on the viability of T. gondii bradyzoites in raw and dry-cured ham. Meat of pigs experimentally exposed to 4000 oocysts of T. gondii VEG strain was vacuum-packaged and subjected to high pressure processing (HPP). Tap water (6 degrees C +/- 1 degrees C) was used as the pressure-transmitting fluid, and its temperature during HPP increased 2.7 degrees C per 100 MPa. The effect was evaluated by bioassay in mice followed by qPCR. In raw ham, 100-400 MPa/1 min did not inactivate T. gondii, whereas 600 MPa/20 min was effective. In dry-cured ham, 600 MPa for 3 or 10 min were not effective and a 20-min treatment was required to render the bradyzoites noninfectious for mice. Our results point toward the potential use of HPP as a tool for risk control of T. gondii and as a food safety guarantee.