Physical properties and optimization of bio film prepared with corn starch and Justicia adhatoda leaf extract

Abstract

Justicia adhatoda leaves rich in antioxidant properties was used in increasing the edible films (EFs) functionality. In the present study, physical properties of the corn starch based EFs prepared with different concentration of sucrose, glycerol and J. adhatoda leaf extract were analyzed. The thickness of the EF ranged between 98–142 μm and increased significantly with the addition of sucrose and glycerol. Opacity (17.50–24.63%) of the film was significantly increased by the addition of J. adhatoda leaf extract. Increase in concentration of sucrose and glycerol had decreased the tensile strength (11.42 to 4.85 MPa) and increased the water vapor permeability (4.5 x 10−7 to 19 x 10−7 g.m−1pa−1). Water solubility of the films varied from 37.14 to 47.58% and it was significantly influenced by the concentration of glycerol. Film formulation at 1.14% sucrose, 21.00% glycerol and 3.00% Justicia adhatoda leaf extract was considered to be the optimized film formulation for EF preparation.