Modeling and analysis of film composition on mechanical properties of maize starch based edible films

The present study investigates the influence of composition (content of maize starch (1–3 g), sorbitol (0.5–1.0 ml), agar (0.5–1.0 g) and tween-80 (0.1–0.5 ml)) on the mechanical properties (tensile strength, elongation, Young's modulus, puncture force and puncture deformation) of the maize starch based edible films using four factors with three level Box–Behnken design. The edible films were obtained by casting method. The results showed that, tween-80 increases the permeation of sorbitol in to the polymer matrix. Increasing concentration of sorbitol (hydrophilic nature and plasticizing effect of sorbitol) decreases the tensile strength, Young's modulus and puncture force of the films. The results were analyzed by Pareto analysis of variance (ANOVA) and second order polynomial models were obtained for all responses with high R2 values (R2 > 0.95). 3D response surface plots were constructed to study the relationship between process variables and the responses.