Biopolymers

Varieties of renewable biopolymers such as polysaccharides were obtained from plant have been investigated for the development of edible/biodegradable non petrochemical-based packaging materials and edible coatings. Alcayota (Curcubita ficifolia) is an interesting alternative to synthetic gas-barrier polymers in packaging applications. The films have low gas permeability under dry conditions due to their high contents of hydrogen bonds. The films were prepared from water solution of hydrolyzed alcayota gum (Alc-OH). The film of Galc-OH properties are mainly due to the strong hydrophilicity. In order to improve water resistance, the films were modified using glutaraldehyde (Glu). The films of Galc-OH were immersed in solutions Glu for a period of 12 and 24 hours (Alc-OH-12G and Alc-OH-24G). The crosslinked films providing a water vapor permeability (WVP) values in the range from 2.32 to 1.59x10-10 g m/m2 s Pa and mechanical properties expressed in elastic modulus from 336.86 to 465.41MPa. The X-ray diffraction showed amorphous and shift to lower d-spacing, i.e. at lower distances between the polysaccharide chains. These crosslinked membranes exhibit excellent water resistance, low O2 permeation, which make them very useful in selecting biodegradable films.