The observed behavior could be due to that in the initial stage it
exists more difference between the chemical potential of the fruit
and osmotic solution and, for consequence, it exists more water
loss and solids gain, permitting that the diffusion of the molecules
is quicker. The decreasing rates could be attributed to a decrease in
the concentration gradient and structural changes that occur in the
tissues, slowing the diffusion process.
The used solution:samples mass relation avoid changes in osmotic
solution concentration during the dehydration process,
therefore, changes in concentration gradient are due to the changes
in the fruit.
3.3.2. Process efficiency
The main characteristic of an osmotic dehydration process is
the loss of water; however, the solids gain is a parameter to consider,
because the process efficiency depends on these two parameters.
The weight reduction is also considered an important
parameter in order to measure the efficiency of the osmotic
process.
3.3.2.1. Water loss. Fig. 1 shows the changes in the water loss during
the osmotic dehydration process of green and ripped papaya