Inactivation Kinetics of Listeria monocytogenes by High-Pressure Processing: Pressure and Temperature Variation
Article first published online: 2 JUL 2012
Journal of Food Science © 2012 Institute of Food Technologists® No claim to original US government works
Journal of Food Science
Volume 77, Issue 8, pages M458–M465, August 2012
How to Cite
Doona, C. J., Feeherry, F. E., Ross, E. W. and Kustin, K. (2012), Inactivation Kinetics of Listeria monocytogenes by High-Pressure Processing: Pressure and Temperature Variation. Journal of Food Science, 77: M458–M465. doi: 10.1111/j.1750-3841.2012.02791.x
- Issue published online: 3 AUG 2012
- Article first published online: 2 JUL 2012
- MS 20120072 Submitted 1/13/2012, Accepted 4/27/2012.
- enhanced quasi-chemical kinetics (EQCK) model;
- food safety;
- high-pressure processing (HPP);
- Listeria monocytogenes inactivation kinetics;
- predictive microbiology
Abstract: The enhanced quasi-chemical kinetics (EQCK) model is presented as a methodology to evaluate the nonlinear inactivation kinetics of baro-resistant Listeria monocytogenes in a surrogate protein food system by high-pressure processing (HPP) for various combinations of pressure (P= 207 to 414 MPa) and temperature (T= 20 to 50 °C). The EQCK model is based on ordinary differential equations derived from 6 “quasi-chemical reaction” steps. The EQCK model continuously fits the conventional stages of the microbial lifecycle: lag, growth, stationary phase, and death; and tailing. Depending on the conditions, the inactivation kinetics of L. monocytogenes by HPP show a lag, inactivation, and tailing. Accordingly, we developed a customized, 4-step subset version of the EQCK model sufficient to evaluate the HPP inactivation kinetics of L. monocytogenes and obtain values for the model parameters of lag (λ), inactivation rate (μ), rate constants (k), and “processing time” (tp). This latter parameter was developed uniquely to evaluate kinetics data showing tailing. Secondary models are developed by interrelating the fitting parameters with experimental parameters, and Monte Carlo simulations are used to evaluate parameter reproducibility. This 4-step model is also compared with the empirical Weibull and Polylog models. The success of the EQCK model (as its 4-step subset) for the HPP inactivation kinetics of baro-resistant L. monocytogenes showing tailing establishes several advantages of the EQCK modeling approach for investigating nonlinear microbial inactivation kinetics, and it has implications for determining mechanisms of bacterial spore inactivation by HPP.
Practical Application: Results of this study will be useful to the many segments of the food processing industry (ready-to-eat meats, fresh produce, seafood, dairy) concerned with ensuring the safety of consumers from the health hazards of Listeria monocytogenes, particularly through the use of emerging food preservation technologies such as high-pressure processing.