*2.8. Data Analysis*

First order kinetics was fitted to the logarithm of the concentration of viable cells [24]. The decimal reduction times (D, min) were estimated to describe the effect of process time on the viability loss of the tested microorganisms. The effect of temperature was expressed through the thermal resistance constant (zT), and the effect of pressure was described by the pressure resistance constant (zP) [24]. The parameters of the proposed mathematical model, which describes the viability loss of the microorganisms as a function of pressure and temperature, were estimated using non-linear regression on SYSTAT 10.0 software (SYSTAT 10.0 Statistics, 2002, SPSS Inc., Chicago, USA).
