Analysing the lag–growth rate relationship of Yersinia enterocolitica

A generalised z-value concept has been applied to analyse the relationship between the lag and the growth rate of Yersinia enterocolitica at a range of temperature, atmospheric carbon dioxide and oxygen percentages. The product of the specific growth rate and the lag (the “work to be done” during the lag phase) is found to be independent of temperature. However, it does depend on the CO 2 and O 2 concentrations, though the effect of oxygen was less noticeable than the effect of carbon dioxide.