Abstract
This thesis demonstrated the feasibility of the elaboration of granules with insecticide properties due to a controlled release of essential oils (EOs). Two different process were used for the granules elaboration. Process A consisted in the encapsulation of EO via impregnation on a porous matrix elaborated by two mainly operatory units (extrusion and drying) Process B consisted in the encapsulation of EO during extrusion. A hydrotextural approach was employed to monitor the transformations induced to the granular material by the thermal- chemical-hydric-mechanical involved processes. The hydrotextural approach demonstrated that it is possible to predict the texturing properties (compactness) and EO charge that the in the granules. The elaboration and encapsulation processes used in the granules elaboration had a direct impact on the retention and release of the EO and in the interactions of the EO with the matrix. The granules’ insecticide efficiency proved to have a direct relation with the hygroscopic and temperature conditions found during infestation. The elaboration and encapsulation processes need to be optimized. Finally, the presence of residual EO was analyzed in the milling products of wheat grain after contact with the granules. Coarse bran had higher traces of EO than flour, however the amount of aroma compounds found in flour would not affect the end quality of the product