New insight into the glycerol plasticizer concentration effect on the properties and microstructure of soluble Tremella fuciformis polysaccharide edible films
Qian Lin, Yanan Zhou, Shuang Ma, Sijie Lin, Yuele Cai, Zhanhong Huang, Song Miao, Lu Xu
Abstract
• Formulation of TFP films with superior mechanical properties were optimized • Glycerol was beneficial in maintaining the ordered structure of films • High elasticity and brittleness films were achieved with appropriate concentrations • Non-purified and purified polysaccharide films were compared • Purified films shown reduced barrier properties against water vapor and UV radiation Glycerol was used as a plasticizer to prepare thin films of Tremella fuciformis polysaccharide (TFP) in order to explore edible polysaccharide films. The effect of 10-14% (w/w, on a dry basis of the weight of TFP) glycerol on the morphological structure, physical properties and mechanical properties of the formed films was systematically evaluated to probe the interactions within the film system. At the optimum concentration of glycerol addition (13%), the films showed smooth and uniform surface, no cracks in the cross-section, and enhanced mechanical properties, showing good molecular compatibility. The TFP purification resulted in improved appearance, uniformity, and hydrophilicity of the polysaccharide films (13% glycerol) significantly increasing the elongation at break (134.97% times of that of the unpurified polysaccharide). FTIR spectroscopy and DMA results indicate that the addition of appropriate glycerol concentration helps to form a denser hybrid system structure and enhance the viscoelastic properties and thermal stability of the films. This study expands the potential applications of TFP and provides the scientific foundation for the development and performance optimization of green modified materials.