Development and characterization of active gelatin-chitosan packaging incorporated with guava leaf extract for extending meat shelf life

Abstract

Biopolymer films (biofilms) were evaluated for suitability in meat packaging applications. Polyesters, proteins, and carbohydrates are among the most commonly utilized materials for producing bioplastics due to their mechanical properties, which closely resemble those of conventional plastics. However, these properties are significantly influenced by the film's composition, molecular weight, solvent type, pH, component concentration, and processing temperature. Conventional plastic films, including microplastics, are non-bioactive and contribute to persistent pollution. This underscores the importance of developing novel materials that incorporate bioactive plant compounds to endow plastic films with antimicrobial and antioxidant functionalities. In this study, two gelatin-chitosan films were fabricated: one without any extract and another incorporating guava leaf extract. These films were characterized to determine their optical, mechanical, morphological, and thermal properties. Additionally, a microbiological analysis was conducted to assess the impact of polymeric biofilm packaging on the shelf life of beef. Both films exhibited favorable tensile strength values (24.74–27.12 MPa), high transparency (0.79–1.18), and effective barrier properties against water vapor (8.95–9.29 × 10⁻⁸ g·mm·Pa⁻1 h⁻1 m⁻2) and oxygen (9.7–9.10 × 10⁻1⁸ m³·m⁻2 s⁻1 Pa⁻1). During storage, the biofilm containing guava leaf extract demonstrated a reduction in microbial growth, and this enhanced the beef’s color stability. In conclusion, biopolymeric films incorporating guava leaf extract demonstrated notable antioxidants and antimicrobial properties, effectively inhibiting microbial growth, preserving the physical quality of beef, and significantly extending its shelf life under refrigerated conditions.