Food Hydrocolloids 25 (2011) 879-886
Quinoa protein/chitosan films were obtained by solution casting of blends of quinoa protein extract (PE)
and chitosan (CH). Films from a PE/CH blend were characterized by FTIR, X-ray diffraction, thermal
analysis, and SEM. The tensile mechanical, barrier, and sorption properties of the films were also evaluated.
The blend of PE with CH yielded mechanically resistant films without the use of a plasticizer. The
film had large elongation at break, and its water barrier properties showed that they were more
hydrophilic than CH film. The thickness and water-vapor permeability of PE/CH (v/v) 1/1 blend film
increased significantly compared to pure CH films. CH films are translucent in appearance and yellowish
in blend with PE. By blending anionic PE with cationic CH an interaction between biopolymers was
established with different physicochemical properties from those of pure CH. Drying and sorption
properties show significant differences between PE/CH blend film and CH film. The structural properties
determined by XRD, FTIR and TGA showed a clear interaction between quinoa proteins and CH, forming
a new material with enhanced mechanical properties.