Films of chitosan and gelatin were prepared by casting their aqueous solutions (pH < 4.0) at 608C and evaporating at 22 or 608C (low- and
high-temperature methods, respectively). The physical (thermal, mechanical and gas/water permeation) properties of these composite films,
plasticized with water or polyols, were studied. An increase in the total plasticizer content resulted in a considerable decrease of elasticity
modulus and tensile strength (up to 50% of the original values when 30% plasticizer was added), whereas the percentage elongation
increased (up to 150% compared to the original values). The low-temperature preparation method led to the development of a higher
percentage renaturation (crystallinity) of gelatin which resulted in a decrease, by one or two orders of magnitude, of CO2 and O2 permeability
in the chitosan/gelatin blends. An increase in the total plasticizer content (water, polyols) of these blends was found to be proportional to an
increase in their gas permeability