The effect of growth temperature, process temperature, and sodium chloride on the high-pressure inactivation of Listeria monocytogenes on ham

• Published in: European food research & technology Vol. 242; no. 12; pp. 2021 - 2029
• Main Authors: Teixeira, Januana S., Maier, Maximilian B., Miller, Petr, Gänzle, Michael G., McMullen, Lynn M.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2016; Springer Nature B.V
• Subjects: Agriculture; Analysis; Analytical Chemistry; Antimicrobial agents; Bacteria; Biotechnology; Chemistry; Chemistry and Materials Science; Chloride; Cold; Cooking; Experiments; Food; Food matrix; Food Science; Forestry; Heat treating; High temperature; Inactivation; Listeria; Listeria monocytogenes; Meat; Original Paper; Pressure vessels; Proteins; Sodium; Sodium chloride; Studies; Temperature; Growth temperature; Ready-to-eat meat; Inactivation; High-pressure processing; Treatment temperature
• ISSN: 1438-2377; 1438-2385
• DOI: 10.1007/s00217-016-2700-6

This study investigated the effect of growth temperature (8–32 °C), process temperature (−17 to 32 °C), and sodium chloride concentration (0–3 %) on the lethality of pressure to Listeria monocytogenes . Pressure treatments were performed using a 5-strain cocktail of L. monocytogenes . Cultures grown at 8 °C were more resistant to pressure than cultures grown at 20 or 32 °C. Pressure treatments of the Listeria cocktail indicated that Listeria were most resistant to pressure at −5 or +5 °C. The effect of pressure was further evaluated at 500 MPa and +5 °C in buffer containing 1 or 3 % NaCl. Cultures treated in the presence of 3 % NaCl were more resistant than cultures treated in the presence of 1 % NaCl. Results obtained in buffer were compared to treatment of cooked ham containing 1 or 3 % NaCl. L. monocytogenes was more resistant in ham with 3 % NaCl when compared to ham with 1 % NaCl. L. monocytogenes grown at 32 °C were slightly more resistant to pressure when compared to cultures grown at 8 °C. Refrigerated storage of treated samples for 4 weeks demonstrated that L. monocytogenes recovered from all treatments with a pressure-holding time of 8 min or less. In conclusion, the effect of high-pressure processing strongly depends on growth temperature, process temperature, and the food matrix. To generally achieve a 5-log reduction of L. monocytogenes on ready-to-eat meats, combinations of pressure with elevated temperature or other antimicrobial hurdles are necessary.