n this investigation, Eremurus luteus root gum (ELRG) films with different contents of glycerol and sorbitol (30, 40, and 50% w/w) as plasticizers were fabricated by casting method. The storage stability of these films was analyzed in two simulated common food storage conditions. For this purpose, the influence of storage time (30 and 60 days) and storage conditions (25 °C-50%RH and 4 °C-75%RH) on some physical, optical, color, barrier, mechanical, and microstructure characteristics of the films were investigated. The results revealed an increase in thickness, opacity, tensile strength, elongation at break (%) and water vapor permeability of plasticized films with growing storage time. The results of the mechanical analysis revealed lower tensile strength and elastic modulus and higher elongation at break (%) for glycerol-plasticized ELRG films than sorbitol-contained films during storage at both conditions. SEM micrographs indicated roughness with slight holes and break in the surface of stored plasticized ELRG films at 25 °C after 60 days compared with films on the initial day. The highest changes in structure and surface morphology with the extension of storage time were observed in sorbitol-plasticized film. The outcomes of the present study indicated the instability of ELRG film characteristics in both conditions and could be recommended as edible packaging for food products within a specific time frame.

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