Edible composite films based on konjac glucomannan, chitosan and carboxymethyl cellulose sodium

Edible composite films were prepared from konajc glucomannan (KGM), chitosan (CTS) and carboxymethyl cellulose sodium (CMC-Na). The permeability and mechanical properties of the films as a function of compositions, pH, plasticizer, drying temperature were tested. CMC-Na increased while KGM and CTS decreased the water permeability with their using quantity increasing. Glycerol as plasticizer also increased the water permeability. An increase in water permeability appeared to be associated with an increase in elongation and a decreasing in tensile strength as affected by the composition and plasticizer. The water permeability increased with increasing temperature accompanied by increased tensile strength and decreased elongation. Our study shows that at the ratio of KGM:CTS:CMC-Na of 1:2:1, pH 1-2, glycerin content of 1.5%, and the drying temperature of 40°C, the edible film exhibited best mechanical properties and water barrier capacity.