The aim of this work was to test the performance of antimicrobial-effective phenolic extracts in combination with biopolymer chitosan for the functionalization of active food packaging material. Particles of the extracts were encapsulated in chitosan biopolymer particles and dispersed in a macromolecular chitosan solution. Formulations were then applied as two-layer chitosan coatings of polylactic acid (PLA) films with the rolling method. The physical and chemical deposition of the formulations to the foil surface was monitored by ATR-FTIR and XPS analyses, which clearly showed the presence of functional groups and the chemical composition of the extracts and chitosan on the surface. The wettability was monitored with contact angle measurements, which decreased in all cases and thus contributed to the anti-fog foil properties, which are extremely important for practical use. In the desorption experiment with ATR-FTIR and XPS analysis, we detected the migration of elements from the surface of the foils, which indicates the instability of the coatings. The results of the SEM analysis confirm the coverage of the foils with different coatings, but simultaneously reveal the inhomogeneity of the coating, which could be improved by changing the coating technology. The newly developed functionalized films show good antioxidant properties and more than 95,0 % antimicrobial activity against the pathogenic bacteria Staphylococcus aureus. Functionalization of PLA films with biopolymer coatings with chitosan enriched with selected phenolic extracts was successful while providing hydrophilic, antioxidant, and antimicrobial properties.
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