The quality of the dried products could be improved by decreasing the drying temperature
or the drying period.
Therefore, instead of oven or convective drying,vacuum drying is widely preferred. Moreover, some pretreatments are used in order to speed up the drying process.
Ultrasound treatment
is widely used as a pretreatment technique to accelerate drying.
Applying ultrasound interrupts the continuity of themembranes, and thus increases
the mass transfer rate between the cell and its extracellular surroundings.