Characterization of basil seed gum-based edible films incorporated with Zataria multiflora essential oil nanoemulsion.

Direct introduction of essential oils (EOs) into biopolymer-based packaging materials faces various challenges such as insolubility and loss of activity. The aim of this study was increasing the bioactivity of Zataria multiflora essential oil (ZMEO) through first making a nanoemulsion and then immobilizing within basil seed gum (BSG)-based film network. ZMEO (nano)emulsions were prepared using high intensity ultrasound approach at 150W and various sonication times (0, 2.5, 5 and 10min). An increase in the antibacterial activity of ZMEO nanoemulsion was observed by decreasing the nanoemulsion droplet size. Increasing nanoemulsion concentration in BSG film matrix improved the mechanical properties. Scanning electron micrographs showed that the presence of ZMEO nanoemulsions resulted in significant changes in the microstructure of BSG films. Antimicrobial films were effective against potential foodborne pathogens. This innovative incorporation of EOs into biopolymer-based films may have implications in extending the shelf life of food products through retarding the release of volatile constituents.