Model for combined effect of temperature and salt concentration/water activity on the growth rate of Staphylococcus xylosus

Publisher Website
Google Scholar
Abstract
The combined effect of temperature and NaCl concentration/water activity on the growth rate of a strain of halotolerant Staphylococcus is described by the square-root models which had been used previously to model temperature dependence only. The model .sqroot.+r = b(T-Tmin) is shown to be a special case of Belehradek temperature function which is given by r = a(T-.alpha.)d. The constant .alpha. is the so called ''biological zero'' and equivalent to Tmin in the square-root models. This and the exponent d = 2 were unffected by changing NaCl concentration/water activity. The Belehradek-type equations are preferable to the Arrhenius equation in that their parameters do not change with temperature. The constancy of Tmin allows deviation of a simple expression relating growth rate of strain CM21/3 to temperature and salt concentration/water activity within the range of linear response to temperature predicted by the square-root model.