Osmotic dehydration induced structural changes in apple tissues,
affecting rheological properties. Osmotically dehydrated apples
became soft, extensible and lost crispness and hardness. The
behavior of the moduli G0 and G00 indicated weaker gels after osmosis.
There was an abrupt change in compression properties of the
tissues after osmotic dehydration at aw 0.97, while reduction to
aw 0.94 lead to mechanical properties more similar to those of
fresh apples. The nature of the sugar employed and the aw level significantly
affected the compression behavior and the state and distribution
of water in apple tissues, while in general mechanical
spectra and creep analysis were not sensitive enough for distinguishing
physical differences between treatments assayed. Some
macroscopic rheological parameters could be linked to changes
at microscopic level