Mechanical and physico - chemical properties of biodegradable protein-based films: A comparative study

Abstract

Biodegradable protein-based films were prepared using the commercial gelatin (bovine hide) (CG), giant catfish skin gelatin (GG), soy protein isolates (SPI) in comparison with commercial wrap film (polyvinyl chloride; PVC). The physical, chemical and mechanical properties of the resulting films were determined and compared. The molecular weight distributions of the GG had high quantities of α-chains and β-components. The GG film had higher mechanical properties [tensile strength: TS 26.42 MPa and elongation at break: EAB 128.25 (%)] but lower thickness (0.0454 mm) than those protein-based films. The PVC film had higher mechanical properties [TS: 44.93 MPa and EAB: 253.71 (%)] but lower water vapor permeability [3.37x10-6 g·mm·h-1·cm-2·Pa-1], film thickness [0.0103 mm] and film insolubility than protein-based films. The film appearance of protein-based films was similar to commercial wrap film with uniform transparency.