title: Effect of γ-irradiation on the physical and mechanical properties of kefiran biopolymer film.
abstract: In this study, the effect of different γ-ray dosages (3, 6, and 9 kGy) on the functional properties of kefiran biopolymer was investigated. The obtained results showed that increasing γ-ray dosage brought about an increase in the tensile strength of film specimens up to three-times. However, elongation at break, and tensile energy to break of γ-irradiated kefiran films decreased in the wake of increasing γ-ray dosage. γ-Irradiation could improve surface hydrophobicity, sensitivity of kefiran film specimens to water, and water vapor permeability, but yellowness of films increased, simultaneously. XRD spectrum confirmed increased crystallinity of γ-irradiated films. Melting point of films was constant but glass transition temperature decreased drastically at high γ-ray dosage (9 kGy). ATR-FTIR analysis confirmed that γ-ray engendered no changes in chemical functional groups. According to the result, a mechanism was proposed to percept the effects of γ-irradiation on kefiran biopolymer and its role on the functional properties of kefiran film. Hence, the functional properties of kefiran films were depend on the ratio of cross-linkages between polymer chains and produced mono and disaccharide by γ-irradiation.
authors.affiliation: Department of Food Science and Technology, Faculty of Agriculture, University of Zanjan, 45371-38791 Zanjan, Iran. Electronic address: i.shahabi@znu.zc.ir.
authors.forename: Iman
authors.initials: I
authors.lastname: Shahabi-Ghahfarrokhi
authors.affiliation: Department of Food Science and Engineering, Campus of Agriculture and Natural Resources, University of Tehran, P.O. Box 4111, Karaj, Iran.
authors.forename: Faramarz
authors.initials: F
authors.lastname: Khodaiyan
authors.affiliation: Department of Food Science and Engineering, Campus of Agriculture and Natural Resources, University of Tehran, P.O. Box 4111, Karaj, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Mousavi
authors.affiliation: Department of Wood Engineering and Technology, Gorgan University of Agricultural Sciences and Natural Resources, 4913815739 Gorgan, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Yousefi
mesh_terms: D001704:Biopolymers / Q000737:chemistry*; D005720:Gamma Rays; D055595:Mechanical Phenomena; D010539:Permeability; D011134:Polysaccharides / Q000737:chemistry*; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water; D014961:X-Ray Diffraction
chemical_list: D001704:Biopolymers; D011134:Polysaccharides; D014867:Water; C050180:kefir grain polysaccharide
keywords: Kefiran; Mechanism; γ-Irradiation