Physicochemical Properties of Edible and Preservative Films from Chitosan/Cassava Starch/Gelatin Blend Plasticized with Glycerol

Edible films from chitosan, cassava starch, and gelatin plasticized with glycerol have been developed by casting method, and the effects of cassava starch (50, 100 and 150 g per 100 g of chitosan), gelatin (0, 25 and 50 g per 100 g of chitosan) and glycerol (21, 42 and 63 g per 100 g of chitosan) from the film solution on various properties of chitosan-based films have been studied using response surface methodology (RSM). The possible interactions between the major components were evaluated by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The properties of the resulting chitosan-based blends for films were greatly influenced by the incorporation of cassava starch, gelatin and glycerol. The introduction of gelatin and gelatinized cassava starch suppressed the semicrystalline peaks of chitosan films. The amino peak of gelatin shifted from 1542 to 1559 cm, and the NH and/or OH peak of gelatin, cassava starch and chitosan films shifted from 3384, 3414 and 3421, respectively, to 3422 cm in the composite film. These results indicate that there was an interaction and molecular miscibility among the major components. The growth inhibition of phytopathogen on mango fruit surface indicated the efficiency of these coatings and they can be applied for the conservation of fresh or minimally processed fruits and vegetables.