Sustainable Active Food Packaging from Poly(lactic acid) and Cocoa Bean Shells

Area of Science:

• Materials Science
• Polymer Science
• Sustainable Materials

Background:

• Poly(lactic acid) (PLA) is a biodegradable polymer with amorphous characteristics.
• Cocoa bean shells (CBS) are an underutilized agricultural byproduct with potential for material applications.

Purpose of the Study:

• To develop sustainable biocomposites from PLA and CBS.
• To investigate the effect of CBS concentration on PLA composite properties.
• To evaluate the suitability of PLA/CBS composites for active food packaging.

Main Methods:

• Solvent mixing of PLA with varying concentrations of CBS powder.
• Solution casting to form composite films.
• Characterization of physical, barrier, antioxidant, and biodegradability properties.

Main Results:

• CBS inclusion increased PLA crystallinity and Young's modulus by up to 80% while maintaining plasticity.
• Composites exhibited low water vapor permeability and reduced oxygen permeability, dependent on CBS content.
• CBS conferred antioxidant activity and enhanced biodegradability in aquatic environments (70% in 30 days).
• Low migration levels were observed in food simulants.

Conclusions:

• PLA/CBS biocomposites offer improved mechanical and barrier properties.
• The material demonstrates antioxidant and enhanced biodegradability characteristics.
• PLA/CBS composites are a promising sustainable alternative for active food packaging.