Tannic acid/polylactic acid-grafted maleic anhydride/polylactic acid active packaging for peach preservation

Area of Science:

• Materials Science
• Polymer Science
• Food Science

Background:

• High-performance active packaging requires high active substance loading and preserved material properties.
• Poor compatibility between tannic acid (TA) and polylactic acid (PLA) hinders effective active loading and degrades film performance.

Purpose of the Study:

• To investigate the use of polylactic acid-grafted maleic anhydride (PLA-g-MAH) as a compatibilizer for enhancing TA incorporation into PLA.
• To evaluate the performance of the resulting composite films and their efficacy in preserving peaches.

Main Methods:

• Incorporation of PLA-g-MAH as a compatibilizer in PLA films with varying TA concentrations.
• Evaluation of mechanical properties (tensile strength) and barrier properties (oxygen permeability).
• Assessment of antioxidant activity (DPPH scavenging) and antibacterial capability against Staphylococcus aureus.
• Testing efficacy in extending the shelf life of peaches by monitoring quality parameters.

Main Results:

• PLA-g-MAH enabled a 50% increase in TA loading within PLA films.
• Compatibilized films (MPLA-TA) exhibited significantly improved tensile strength and reduced oxygen permeability compared to uncompatibilized films (PLA-TA).
• MPLA-TA films demonstrated high antioxidant and antibacterial activity, leading to a 200% extension in peach shelf life by delaying quality deterioration.

Conclusions:

• PLA-g-MAH effectively improves PLA-TA compatibility, allowing high active loading and enhanced mechanical/barrier properties.
• The developed MPLA-TA composite films show significant potential for active food packaging applications, particularly for extending the shelf life of perishable fruits like peaches.