Control of Listeria monocytogenes in Ready-to-Eat Meats using Cetyl Pyrindium Chloride (CPC) and Shelf Life Extension of RTE Meats Treated with CPC

This research proposed to optimize and validate the application parameters (spray, temperature, pressure and contact time) of the antimicrobial cetyl pyrindium chloride (CPC) for three types of meat products for the destruction of Listeria monocytogenes using inoculated challenge studies. The shelf life extensions achieved by using CPC spray were evaluated using non-inoculated products, under commercial display conditions. Product microbiological shelf life, along with product quality characteristics such as visual and instrumental color, and purge rate were evaluated.<p>
CPC spray using variable application parameters (temperature, pressure and time) was evaluated for its effectiveness in reducing Listeria monocytogenes inoculated on the surface of commercial frankfurters. Frankfurters were inoculated with a five strain cocktail of L. monocytogenes (101M, 109, 108M, serotype 4c ATCC and serotype 3 ATCC) and subjected to no treatment, CPC treatment and CPC followed by water treatment. One percent CPC was applied to the frankfurters by spraying in a spray cabinet (KSU, Manhattan, KS) with variable parameters (25C, 40C and 55C spray temperatures; 20 psi, 25 psi and 35 psi spray pressures; and 30 second, 40 second and 60 second time of exposure). From initial inoculum levels of 8.20 log CFU/g, one percent CPC reduced L. monocytogenes levels varying by 1.19 to 2.39 log CFU/g. No individual effect of any particular application parameter (p>0.05) was observed on the reduction of L. monocytogenes.<p>
Based on the preliminary results above, and in order to make results more applicable to the RTE meat industry, KSU requested an extension of the project timeline and approval of modified project objectives. The revised project objectives include a low inoculum level of L. monocytogenes to reflect "realistic" contamination levels and evaluation of the reductions in L. monocytogenes populations over the shelf life of the RTE meat products treated with one spray temperature, pressure and exposure time.