We observe the absence of “phase 0” showing a growing allure and “phase 1” with the constant appearance in the drying process of thyme.
Indeed, the warm-up phase (phase 0) disappears when the product is in particles or sheets and the constant speed drying time (phase1) is not observed in many cases when it comes to plant products
In addition, Fig. 3 shows that through the drying period and at a constant drying volume flow rate, a higher drying air temperature produced a decrease of drying time.
Moreover, the rise of the drying volume flow rate decreases the drying time at a constant temperature.
The increase of temperature and drying volume flow rate boost the rate of heat getting in touch with the product and
heighten the water migration.