Effect of Commonly Used Enhancement Solutions on the Viability of Toxoplasma gondii Tissue Cysts in Pork Loin

Abstract

Retail meat cuts of pork are frequently enhanced with salt solutions to improve flavor and texture and to extend shelf life through reductions in microbial contamination. A study of the effect of commonly used meat enhancement solutions on the viability of Toxoplasma gondii tissue cysts was performed using tissues from experimentally infected mice and pigs. Brains of T. gondii–infected mice were injected to 110% of the original weight of the brain with solutions containing sodium chloride (1 and 2%), sodium diacetate (0.1 and 0.2%), sodium tripolyphosphate (0.25 and 0.5%), potassium lactate (1.4 and 1.96%), or sodium lactate (1.4, 1.5, and 2.0%) alone or in combination and stored at 4°C for 7 days before feeding to T. gondii–seronegative cats. Loins were collected from pigs experimentally infected with T. gondii and injected as above and stored for 7, 28, or 45 days at 4°C before feeding to T. gondii–seronegative cats. Cat feces were examined for 14 days to assess oocyst shedding. The present study demonstrated that injection of mouse brains or pork loins with solutions containing 2% sodium chloride or ≥1.4% potassium or sodium lactate, alone or in combination with other components, prevented transmission of T. gondii to cats.