The Effect Of Different Plasticizers On The Physicochemical Properties of Starch Film Incorporated With Pomegranate (Punica granatum) Peel Powder

Abstract

This research studies the effect of different plasticizers on the physicochemical properties of starch film incorporated with pomegranate peel powder. The objective was to evaluate the impact of various plasticizers on the physical, mechanical, and barrier properties of starch-based films. Film samples were prepared using five plasticizer ratios (4:0, 3:1, 2:2, 1:3, and 0:4 of glycerol:sorbitol) and a fixed concentration of PGP powder. The films were produced using the solution casting method. Evaluations included thickness, opacity, water solubility, colour, mechanical properties, biodegradability, and oil permeability. The film thickness increased progressively with higher sorbitol concentrations. The increasing concentration of sorbitol also increased the transparency and water solubility. The different ratios of glycerol and sorbitol did not have a significant effect on the hunter L*, a*, and b* values of the films due to the colourless nature of the plasticizers. The tensile strength and elongation at break of the films were the highest when both glycerol and sorbitol were used. However, increasing concentrations of sorbitol increased the Young’s modulus of the film significantly. All films degraded by day 9 as well as exhibited excellent oil barrier properties. The combination of glycerol and sorbitol exhibits a good balance of mechanical properties and barrier properties.