Temperature dependence of growth kinetics of food bacteria

Abstract

A predictive model is presented that describes the non-Arrhenius behaviour of growth and survival kinetics of food bacteria, in both the growth phase and lag phase of growth as influenced by temperature, in a wide range of foods and media. For independent data spanning 88 years and seven independent researchers, the model gave a very high degree of goodness of fit explaining between 96.1 and 99.9% of the variance accounted for (%V) in the growth phase, and between 95.6 and 99.5% of the %V in the lag time, with an overall mean of 98.4%V. The model is a modified Arrhenius form, formulated from consideration of temperature-dependent chemical rate theory (CRR). This model form has not previously been evaluated for predicting temperature-dependent growth kinetics of bacteria. The model has two terms, namely, 1/T and InT, together with three coefficients. The model has fitted all available data without exception. This very good fit of the predictions of the model to primary data compared very well with the established and widely applied, empirical model form of Davey. Both models imply temperature-dependent Arrhenius parameters for the rate of microbial growth and survival. Both appear very useful to describe practically the non-linear dependence of the rate coefficient for growth, and the lag time, which normally prevents the use of the Arrhenius equation.