Development and optimization of edible corn starch films incorporating citronella essential oil and calcium nanoparticles

Abstract

Edible films (EFs) are thin layers of biodegradable organic materials that serve as an alternative to plastic packaging. These films can be made from proteins, polysaccharides, or lipids, with starch being the major material due to its ability to form effective barriers against gases, along with its high solubility and flexibility. To enhance their functional properties, substances such as citronella oil (AC) are incorporated, providing hydrophobic characteristics, while calcium carbonate nanoparticles (NPCC) reinforce the mechanical properties of the films. This study aimed to formulate EFs using native corn starch, AC, and NPCC, and to evaluate their functional properties. It was conducted in two stages: firstly, the EFs were prepared using the casting technique, assessing different concentrations of AC (0-2%) and NPCC (0-2%) for water vapor permeability (PVA), water solubility (S), tensile strength (σ), elongation (ε), and Young's modulus (E). In the second stage, the formulation was optimized using a numerical response surface method. The results indicated that increasing citronella oil decreased WVP, WS, σ, and E values, however ε was increased. On the other hand, increasing calcium carbonate nanoparticles slightly reduced WVP and WS but enhanced E and σ, while decreasing ε. The optimal processing conditions were 1.38% AC and 1.71% NPCC, achieving a suitable balance between functional properties. This suggests that the edible films are a promising alternative to plastic packaging in the food industry.