Submitted to: National Hog Farmer
Publication Type: Trade Journal
Publication Acceptance Date: December 1, 2004
Publication Date: December 15, 2004
Citation: Hill, D.E. 2004. Meat processing technologies may help block toxoplasma transmission. National Hog Farmer. p. 31
To help consumers reduce the risk of contracting toxoplasmosis from infected pork requires a mutifaceted approach that includes on-farm prevention procedures and processing and preparation procedures.
In studies at the U.S. Department of Agriculture's (USDA) Agricultural Research Service, Beltsville (MD) Agricultural Research Center (BARC), researchers have identified that injection of pork loins with solutions commonly used in meat processing to improve pork quality and palatability can prevent the spread of Toxoplasma gondii, the parasite responsible for toxoplasmosis infections.
The protozoan parasite Toxoplasma gondii infects nearly one-third of the human population. For most adults, it does not cause serious illness. But it can cause blindness and mental retardation in congenitally infected children and devastating disease in immunocompromised individuals.USDA estimates that 50% of toxoplasma infections in the U.S. are linked to consumption of raw or undercooked meat products containing toxoplasma tissue cysts.
Pork for human consumption has been shown to contain high levels of infection with toxoplasma, and can be found in virtually every edible cut at retail. Commonly, retail cuts of pork are enhanced with salt solutions to improve flavor and texture, and to extend product shelf life by reducing microbial contamination. To test the effect of commonly used meat enhancement solutions on the viability of toxoplasma tissue cysts, BARC researchers experimentally infected pigs with the parasite. Loins were collected from the infected pigs and injected to 110% of the original weight of the loin 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%). These solutions were used alone or in combination.
The treated pork loins were then stored for 7, 28 or 45 days at 39 degrees F before feeding to Toxoplasma gondii-seronegative cats.
The feces of cats fed the parasite were examined for 14 days to assess oocyst (parasite eggs) shedding. The study demonstrated that injection of pork loins with solutions of 2% sodium chloride or 1.4% or greater potassium or sodium lactate, alone or in combination with other components, successfully prevented transmission of Toxoplasma gondii to cats.