Production and characterization of films based on blends of chitosan from blue crab (Callinectes sapidus) waste and pectin from Orange (Citrus sinensis Osbeck) peel

The objective of this study was to develop and characterize films based on blends of chitosan and pectin, produced in laboratory scale, from industrial wastes. The chitosan was obtained by termoalcaline deacetylation of chitin, extracted from blue crab (Callinectes sapidus) waste and characterized according to degree of deacetylation (DD) and viscosimetric molecular weight (Mw); and pectin was extracted by conventional heating, from orange (Citrus sinensis Osbeck) peel and characterized according to degree of esterification (DE) and molecular weight (Mw). The Ch:P based films were prepared by the casting method in different Ch:P ratios [0: 100, 25:75, 50:50, 75:25 and 100:0], and compared to two controls [0:100 and 100:0], of commercial pectin and chitosan. Glycerol was used as a plasticizer at concentrations of 0.2 g/g macromolecules. The addition of high concentrations of pectin in the formulations resulted in films with high solubility and an increase in moisture. No significant difference (P > 0.05) in the degree of swelling (DS) and water vapor permeability (WVP) of the films was observed. Ch:P blend films were less stiff and therefore more elastic and flexible than films based on only one biopolymer. The control films presented better results in terms of color, being brighter and less opaque than other film formulations. These data suggest that chitosan or pectin obtained from agro-industrial waste is a potential matrix to produce biodegradable films for future food applications.