APPLICABILITY OF THE DAVEY (LINEAR ARRHENIUS) PREDICTIVE MODEL TO THE LAG PHASE OF MICROBIAL-GROWTH

The empirical and quantitative (linear Arrhenius) model of Davey (1989a) was assessed against a range of published lag phase data, some of which included combined temperature-water activity as influencing factors while others had temperature as the sole influencing factor. For two large (n greater-than-or-equal-to 27) sets of combined temperature and water activity data, the model explained 74.2 and 86.4% of the variation in results, and for eight wide ranging data sets with temperature as the sole factor, it explained between 80.8 and 99.7% of the variation in results, with an overall mean of 95.7%. These published data included both Gram-positive and Gram-negative bacteria and a spore former. The model has four coefficients which can be obtained by relatively unsophisticated users with linear regression analyses on most desk top calculators or personal computers.