Production of starch based biopolymer by green photochemical reaction at different UV region as a food packaging material: Physicochemical characterization.

In current study, the functional properties of modified starch solutions by photochemical reactions as a biodegradable food packaging material were investigated. Starch film-forming solutions were exposed to ultraviolet A (UV-A) and C (UV-C) over different time periods (1, 6, 12, and 24 h). A green method was used to prepare the modified starch films. Hydrophobicity, moisture sensitivity, and water vapor permeability of the starch films, decreased after exposure to UV irradiation up to 12 h. Tensile strength and Young's modulus of the specimens decreased by increasing UV exposure time. Elongation at break, and tensile energy to break of the film specimens were increased, simultaneously. Scanning electron microscopy images demonstrated that most of the films' physical properties were affected by their microstructures. UV-Vis spectrum of the specimens confirmed that UV-protective properties of the irradiated specimens in UV-A, UV-B, and UV-C region have changed in comparison with the control sample. According to the results, UV-irradiation could be considered as a green, easy, and accessible process for modification of starch-based films.