External authors:

• Johanna Fiallos-Nunez ( Pontificia Universidad Catolica de Chile )
• Yaniel Cardero ( Pontificia Universidad Catolica de Chile )
• Gustavo Cabrera-barjas ( Universidad San Sebastian )
• Claudio M. Garcia-Herrera ( Univ Santiago de Chile )
• Matias Inostroza ( Univ Santiago de Chile )
• Miriam Estevez ( Universidad Nacional Autonoma de Mexico )
• Beatriz Liliana Espana Sanchez ( Ctr Invest & Desarrollo Tecnol Electroquim CIDETEQ )

Abstract:

Biopolymer-based films are a promising alternative for the food packaging industry, in which petrochemical-based polymers like low-density polyethylene (LDPE) are commanding attention because of their high pollution levels. In this research, a biopolymer-based film made of chitosan (CS), gelatin (GEL), and glycerol (GLY) was designed. A Response Surface Methodology (RSM) analysis was performed to determine the chitosan, gelatin, and glycerol content that improved the mechanical properties selected as response variables (thickness, tensile strength (TS), and elongation at break (EAB). The content of CS (1.1% w/v), GEL (1.1% w/v), and GLY (0.4% w/v) in the film-forming solution guarantees an optimized film (OPT-F) with a 0.046 +/- 0.003 mm thickness, 11.48 +/- 1.42 mPa TS, and 2.6 +/- 0.3% EAB. The OPT-F was characterized in terms of thermal, optical, and biodegradability properties compared to LDPE films. Thermogravimetric analysis (TGA) revealed that the OPT-F was thermally stable at temperatures below 300 degrees C, which is relevant to thermal processes in the food industry of packaging. The reduced water solubility (WS) (24.34 +/- 2.47%) and the improved biodegradability properties (7.1%) compared with LDPE suggests that the biopolymer-based film obtained has potential applications in the food industry as a novel packaging material and can serve as a basis for the design of bioactive packaging.