Development of hydroxypropyl methylcellulose/sodium alginate blend active film incorporated with Dracocephalum moldavica L. essential oil for food preservation

The present study aimed to fabrication and characterization the hydroxypropyl methylcellulose (HPMC) films containing different concentrations of sodium alginate (0.5, 1, and 3% v/v) and Dracocephalum moldavica L. essential oil (DEO; 1, 3 and 5% v/v) as a biodegradable active packaging system. FTIR analysis confirmed the interaction of alginate groups with the hydroxyl group of HPMC. SEM images indicated that the addition of alginate decreased the size and number of the cracks. As a result, the incorporation of alginate and DEO significantly (p < 0.05) improved the water barrier properties of films and the lowest values of water vapor permeability (.38 x 10(-10) g/m center dot h center dot Pa), moisture content (6.30 +/- 0.08%) and water solubility (29.49 +/- 0.04%) were related to the sample containing 1.5% alginate and 5% DEO. Additionally, blending with alginate significantly (p < 0.05) improved the mechanical properties of the films and the blended film sample with 0.5% alginate showed the highest tensile strength (16.13 MPa). The blend films showed high thickness and whiteness Index. Also, the antioxidant activity of the films was enhanced by incorporation DEO and the highest DPPH scavenging activity (74.58 +/- 2.31%) was attributed to the samples incorporated with 5% DEO. In conclusion, the fabricated blend film showed considerable potential for active food packaging.