Rapid inactivation of bradyzoites during formulation of dry cured ready-to-eat pork sausage.

Curing processes for pork meat in the U.S. currently require individual validation of methods to demonstrate inactivation of , a nematode parasite historically associated with pork. However, for protozoan parasites, no such strictures exist. It has been assumed, with little evidence, that curing processes required to inactivate also inactivate . Currently no model of meat chemistry exists that can be correlated with inactivation of . Given the possibility of the presence of in pork meat, and the frequent use of pork for ready-to-eat (RTE) products not intended to be cooked, curing methods which inactivate early in the curing process would be of great value to producers. In this study, we tested the effect of five variables - salt/brine concentration, water activity (a), pH, temperature, and time on inactivation of bradyzoites in tissue cysts using low and high endpoints for common curing treatments during preparation of dry cured pork sausage. Survival of bradyzoites at each stage of preparation was assessed using a mouse bioassay. Results indicated that encysted bradyzoites do not survive the early stages of the dry curing process within the endpoint parameters tested here, even at levels of NaCl that are lower than typically used for dry curing (1.3%). Exposure of encysted bradyzoites to curing components in the formulated batter resulted in rapid inactivation of bradyzoites. These data suggest that the use of dry curing components may be effective for controlling potentially transmitted through RTE meats, rendering them safe from risk with respect to transmission to human consumers.