demonstrated by absorption
isotherms reported in the literature (Leung, 1986). Moreover, since
sorbitol is more similar to the molecular structure of glucose units
than glycerol, the chances of sorbitol to interact with polymeric
starch chains are higher, thus sorbitol-containing films present
higher intermolecular forces and show lower capacity to interact
with water. Films prepared with rice starch and rice flour presented
similar water sorption isotherms, even for different sorbitol
concentrations (0.20 or 0.30 g/g raw material). Data presented in
Table 1 showed that plasticizer content did not have a significant
influence on the monolayer water content (m0) for each kind of
film. Rice starch films plasticized with glycerol gave the highest
values for monolayer moisture. The parameter k is the corrective
constant taking into account properties of multilayer molecules.