Pullulan-Tween 40 emulsified films containing geraniol: production and characterization as potential food packaging materials

Petroleum-based plastics have been widely used as packaging materials because of their low-cost availability and good mechanical properties. However, the use of plastics has become restricted as they are highly resistant to biodegradation, causing environmental problems. This work aimed to produce and characterize emulsified pullulan films incorporating geraniol for application as food packaging materials with potential to substitute the conventional plastics. When geraniol was incorporated in the films, they showed antimicrobial activity against Enterococcus faecalis ATCC 29212 (inhibition zone diameter = 15.19 ± 0.66 mm) and Pseudomonas aeruginosa ATCC 27853 (inhibition zone diameter = 10.99 ± 1.82 mm). Furthermore, scanning electron microscopy showed the inhibition of Enterococcus faecalis ATCC 29212 biofilms when they were directly formed on the emulsified pullulan films incorporating geraniol. The produced films also demonstrated high transparency (> 90%) and hydrophilic surfaces (water contact angle < 90°). This work demonstrated the viability of using geraniol to produce pullulan active films as new food packaging materials.