depicts the drying rates as a function of moisture ratio.
When product temperature is controlled, the relative drying rates
in the beginning are much higher and decrease much more
significantly than when air temperature is controlled. This can be
explained with the fundamentally different influences of
isothermal and non-isothermal conditions on drying behaviour.
When comparing nearly identical drying times (A60, P47) the drying
rate for P47 is higher than that of A60 until a moisture ratio of 0.4 is
reached. Comparing the temperature developments