Abstract:

In order to establish growth kinetics models for L. monocytogenes in chilled pork, L. monocytogenes were inoculated to contamination-free longissimus muscles to monitor the growth of this species of bacteria during storage. Samples were placed at 2, 15 and 28 ℃ for storage, and total L. Monocytogenes count was determined during different storage periods. Growth kinetics models for L. monocytogenes were developed at various temperatures using Gompertz equation. The relationship between temperature and μmax (maximum specific growth rate) or λ(lag phase) of L. monocytogenes growth in temperature range of 0 －30 ℃ revealed a good linearity evaluated by the square root model with correlation coefficients of 0.716 and 0.972, respectively. The absolute values of model residuals were less than 0.03 and fluctuated around zero, which revealed an absolute reliability of this model. Therefore, this square root model can describle the effect of temperature on growth of L. monocytogenes.

Key words: chilled pork, L. monocytogenes, growth kinetics model