Effect of gamma irradiation on the physicochemical properties of a starch-based film

The influence of gamma irradiation and an addition of locust bean gum (LBG) on the properties of the starch-based films were investigated. The film casting solution including the corn starch, LBG (0%, 0.75%, and 1.5% w/v), polyvinyl alcohol, sucrose, and glycerol was irradiated at 0, 3, 6, 12, and 24 kGy. After irradiation, an intact and smooth film was formed by irradiation treatment. The presence of LBG increased the tensile strength of the films, but the appropriate irradiation dose should be determined to get the highest tensile strength. Application of LBG reduced the percent elongation of the films, but irradiation significantly increased the percent elongation. The enzymatic hydrolysis and water vapor permeability was shown to decrease with an increase in the irradiation dose. Results indicate that the irradiation technology can be a useful tool as a cross-linking agent with starch and LBG to improve the functional properties of a starch-based film. (C) 2006 Elsevier Ltd. All rights reserved.