2.2. Film Preparation
The sugar palm-based films were prepared by conventional solution-casting technique. Glycerol (G), sorbitol (S) or glycerol-sorbitol (1:1) combination (GS) ratio were used as plasticizers to investigate the effect of each individual plasticizer on the developed films. The film preparation procedures are described as follows: Initially, 8% (w/w) aqueous dispersion of gelatinized sugar palm starch was prepared by heating the film forming solution at 95 ± 2 °C for 15 min under constant stirring in a hot water bath. This step helps to provide homogeneous dispersion by disintegrating the starch granules. Thereafter, the different plasticizers were added into the dispersions at 0%, 15%, 30% or 45% (w/w, starch basis). The heating process continued for an additional 15 min at 95 ± 2 °C. The film forming solutions were left to cool down, prior to their casting in glass petri-dishes. The glass petri-dishes served as casting surfaces, enabling the film to have a smooth and flat surface. The fresh casted films were placed in an oven (40 °C) to allow evaporation. All films were prepared in triplicate including films without plasticizers which were used as controls. After 24 h of drying, films were peeled from the casting surfaces and stored in desiccators.
2.3. Tensile Prope