Evaluation of easy-removing antioxidant films of chitosan with Melaleuca alternifolia essential oil

Abstract

Chitosan - tea tree essential oil (TTEO) films were obtained as a new biodegradable material. Malic acid or lactic acid solvents were evaluated to obtain easy-removing films. The microstructure by SEM and FT-IR, the thermal properties by TGA/DSC, the mechanical properties, the water vapor permeability, the antioxidant (DPPH• and ABTS•+) activity and the optical properties of the formulated films were evaluated. A complete dissolution of the film in water was obtained. The elongation to break was higher in the films with malic acid (145.88–317.33%), comparing with those with lactic acid (25.54–44.08%). Chitosan film obtained in malic acid with TTEO showed the highest antioxidant activity. The colour and transparency of the samples did not suffer significant variations by TTEO addition. Films showed good UV-barrier properties, with a slightly improvement by TTEO addition. The films obtained showed a great potential for food packaging applications