Curing conditions to inactivate Trichinella spiralis muscle larvae in ready-to-eat pork sausage

Abstract

Curing processes are one method by which pork products, which are considered ready to eat (RTE) and have not been otherwise tested or treated, can be rendered safe from risk for exposure to Trichinella muscle larvae (ML). Curing processes in the U.S. currently require individual validation of methods to demonstrate inactivation of Trichinella. This is a major undertaking for each process; currently no model of meat chemistry exists that can be correlated with inactivation of Trichinella. Given the potential for new RTE products (e.g., lower salt), the availability of a wider range of tested methods for inactivation of Trichinella in pork would be of substantial value to the industry. In this study, five variables were tested – salt/brine concentration, water activity (aw), pH, temperature, and time, using low and high endpoints for common curing treatments for dry cured pork sausage. The data demonstrated that NaCl concentrations above 1.3%, in combination with fermentation to pH 5.2 or below, resulted in inactivation of >96% of Trichinella ML in stuffed sausages within 24–28 h. All ML were inactivated by 7–10 days post-stuffing. These curing processes reliably predict inactivation of Trichinella spiralis, and can be used within the defined upper and lower endpoint parameters to reduce or eliminate the need for individual product validation.