A combination of gamma irradiation and CaCl2 immersion for a pectin-based biodegradable film

Using citrus pectin a biodegradable film was prepared by a combination treatment of gamma irradiation (0, 10, 20, and 30 kGy) and CaCl2 immersion (0, 5, and 10%) cross-linking. The tensile strength of the pectin-based film was the highest in the 5% CaCl2 treatment at 20 kGy of an irradiation dose. The tensile strength of the film with CaCl2 was generally higher than that of the non-CaCl2 treatment. The elongation at break and water vapor permeability were the lowest at a CaC12 of 5% among the irradiated treatments. The total organic carbon content produced from the Paenibacillus polymyxa and Pseudomonas aeruginosa showed that the film of the 20 kGy-irradiated film was lower than those of the 0, 10, and 30 kGy-irradiated films. In conclusion, irradiation of the film casting solution at 20 kGy combined with a 5% CaC12 immersion resulted in film with improved mechanical properties and biodegradability. (c) 2005 Elsevier Ltd. All rights reserved.