**4. Conclusions**

The analysis of the HILP inactivation curves of the different data sets demonstrated that the application of a Weibull model generally offers a better fit to experimental data than linear model kinetics. Nevertheless, there are some exceptions where neither a first order kinetic nor the Weibull model offers a good fit. On those cases, important deviations from the experimental data might be caused, leading to inaccurate calculation of process parameters, like *Dv* parameter. That is the case of *P. fluorescens* inactivation on mozzarella cheese, where the calculates *Dv* was five times higher than the experimental value.

One advantage of the Weibull model is that despite its empirical nature, its parameters can be correlated to biological phenomena. For instance, the curve shape parameter *n,* that showed in all the kinetics analyzed, the efficiency of the treatment was reduced as the total energy increased, due to different biological factors.

In conclusion, the Weibull model represents a better alternative, in comparison to firs order kinetics models, to describe the inactivation of microorganism by HILP. It also provides further information about the biological phenomena occurring during HILP inactivation process and can be used to calculate other process parameters such as the *Dv* or decimal dose.
