Effect of Chitosan Concentration, Glycerol and Cashew Peel Extract on the Physical, Mechanical and Morphological Properties of Starch‐Based Films

Abstract

ABSTRACTThe present study aimed to optimize the formulation of starch‐based films, exploring the synergy between chitosan (1%, 2% and 3%), glycerol (2.5%, 3% and 3.5%) and concentrated cashew peel extract (1%, 2% and 3%), through a central composite design (23). Evaluating their influence on physical, mechanical and morphological properties. All films produced were flexible and did not present cracks when removed from the plates. Water vapour permeability (WVP) (3.03–7.71 gH2O.mm/m2.h.mmHg) and solubility (1.94%–5.31%) were reduced with the combination of higher levels of extract and chitosan, which also influenced the colour of the films (p < 0.05). Increasing the concentration of cashew peel extract increased tensile strength (TS) and elongation at break (EB) of the films. Morphologically, films with lower levels of cashew peel extract exhibited a uniform and less rough surface. Therefore, our results identified an optimized formulation using the combination of 2% extract, 3% chitosan and 3.5% glycerol. This study expanded the development of starch‐based packaging materials with chitosan, glycerol and the addition of plant extract, which can be used in the preservation of fruits and vegetables.