Abstract
The convective drying could be intensified following different alternatives, for example, by using pretreatments or applying complementary technologies as the assistance of power ultrasound. In this work, the influence of the pretreatment with distilled water (40 min at 25 °C) on convective drying kinetics (40 and 70°C, 1 ms-1) of pineapple slices (2.0 cm diameter, 0.5 cm thickness) was studied. The application of ultrasound during pretreatment (55.5 W/L, 40 kHz) or during convective drying (31 kW m−3; 21.8 kHz) was also addressed. The drying kinetics was modeled with a diffusive model. The results showed that the pretreatment accelerated the later drying process. The application of ultrasound during drying and the higher temperature tested provided the higher values of effective diffusivity identified
