Preparation and characterization of a novel edible film based on Artemisia sphaerocephala Krasch. gum: Effects of type and concentration of plasticizers

Abstract

The aim of this work was to evaluate the influence of type (glycerol, sorbitol and triethyl citrate (TEC)) and concentration of plasticizers, on the physical properties of a novel film from Artemisia sphaerocephala Krasch. gum (ASKG). The results showed that the tensile strength and the light transmission of the film decreased, whereas the elongation at break, the oxygen permeability, and the water vapor permeability of the film increased with increased plasticizer content. It was found that ASKG film containing TEC as plasticizer was brittle and less flexible. Fourier-transform infrared analysis and rheological measurement revealed that plasticizer molecules may disrupt the intermolecular interaction and the entanglement network between ASKG molecules, and form hydrogen bonds with ASKG chains. Thermogravimetric analysis showed that the addition of plasticizer decreased the stability of the film. Scanning electron microscopy showed a homogeneous cross-section of ASKG film with glycerol or sorbitol, however this became porous with the addition of TEC. Among the three plasticizers, sorbitol was found to be the most suitable for the film, making it more flexible and hydrophilic, and the tensile strength of the film reached 29.92–54.04 MPa. It is suggested that ASKG is a promising packaging material, and that ASKG-based film containing sorbitol as a plasticizer has potential as a packaging film.