Osmo-dehydration of fruits

Figure 2. Knudsen desorption isotherms collected from non- treated, partially (one hour treatment) osmodehydrated
apple pulp, and the hypertonic sugar syrup used in the process. mW and mdm stand for water and
dry matter mass, respectively.
Since these quantities can be directly correlated to the RH through the relevant desorption isotherm, one may
describe the shrinkage extent versus RH (Figure 3), which therefore applies to every partial dehydration
level, no matter the way it has been achieved (through osmo-dehydration, or heat drying, or combined
treatment).
Figure 3. Shrinkage of the cells of apple pulp evaluated according to equation 2 (see text). Data from the
Knudsen desorption trend of non- treated samples.