Innovative pre-treatments to enhance food drying: a current review

The application of pre-treatments before drying represents an alternative to better preserve fresh food properties and reduce the energy needs. The aim of this review was to analyse the influence of different pre-treatments (ultrasound, pulsed electric fields, high pressure processing or ethanol) on drying. For this purpose, the effect on food matrices, drying kinetics and different quality parameters has been addressed through the review of the most recent studies. The results can differ greatly depending on the type of pre-treatment and the product considered but, in some cases, an increase in the drying rate and a better retention of quality can be observed. Even so, it is necessary to continue studying these pre-treatments to better understand the effect caused.