Composites of chitosan with acid-soluble collagen from jumbo squid (Dosidicus gigas) by-products

Biodegradable films of chitosan with acid-soluble collagen (ASC) isolated from jumbo squid by-products were prepared using solution-mixing and film-casting techniques. The main goal of the study reported was to evaluate the potential application of ASC as an additive in the preparation of biofilms in composites with commercial chitosan (85% deacetylated, viscosity > 400 MPa s and molecular weight of 570.3 kDa). Thermal properties, scanning electron microscopy (SEM) images, mechanical properties, water vapor barrier properties and water solubility of the films obtained were assessed. SEM images revealed that the surface morphology of chitosan films was influenced by the ASC. The ASC led to a structurewith a less compact morphology than chitosan films. The incorporation of ASC to chitosan induced an increase in the percentage of elongation at break and a decrease of the elastic modulus of films. However, the addition of ASC to chitosan films had a negative effect on the water barrier properties and increased the solubility. The glass transition temperature of chitosan films was found to be ca 159 degrees C and shifted to ca 148 degrees C for ASC/chitosan films containing 50% ASC. ASC from jumbo squid by-products might be useful as a new source of additive in the preparation of biofilms in composites with chitosan. (C) 2011 Society of Chemical Industry