Combining Organic Acid Treatment with Steam Pasteurization To Eliminate Listeria monocytogenes on Fully Cooked Frankfurters

An organic acid solution of 2% acetic, 1% lactic, 0.1% propionic, and 0.1% benzoic acids was combined with steam surface pasteurization to treat frankfurters during vacuum packaging to eliminate potential postcook contamination with Listeria monocytogenes. The thermal lethality of L. monocytogenes from steam was evaluated at an inoculation concentration of 1 to 6 log CFU/cm2. About 3-log reductions of L. monocytogenes were achieved when frankfurters were treated by steam for 1.5 s. Combining organic acid treatment with steam pasteurization further inhibited the growth of surviving L. monocytogenes cells for 19 and 14 weeks when the packaged frankfurters were stored at 4 and 7°C, respectively. The results from this study provide meat processors with useful information for controlling L. monocytogenes on ready-to-eat meats.