Improve properties of sweet potato starch film using dual effects: Combination Mesona chinensis Benth polysaccharide and sodium carbonate

Abstract The effects of Mesona chinensis Benth polysaccharide (MCP) and sodium carbonate (Na2CO3) on the physical, optical, mechanical, thermal, and microstructure properties of sweet potato starch (SPS) film were studied. Rheological results showed that the addition of MCP and Na2CO3 increased the apparent viscosity, and viscoelasticity of the film-forming solution. The addition of MCP and Na2CO3 improved the tensile strength, elongation, and thermal stability of SPS film, and improved the solubility and swelling of SPS film. MCP and Na2CO3 enhanced the ability of SPS film to block ultraviolet radiation. Scanning electron microscope and atomic force microscope results showed that SPS and MCP were good compatible, and the surface of the formed film was smooth and flat. The results showed the addition of MCP and Na2CO3 improved physical properties of SPS film, and then meliorated mechanical and thermal properties, which widened the application of SPS film in the food packaging.