Supercritical CO2 impregnation of Gelatin-Chitosan films with clove essential oil and characterization thereof
Chemical Industry and Chemical Engineering Quarterly
Supercritical CO 2 impregnation process was used for the first time to fabricate biodegradable gelatin-chitosan (G/Ch) films containing clove oil (CO) for potential use in active food packaging. All the impregnations were carried out at moderately low temperature (40 °C). Aiming to maximize CO loading in the films with acceptable morphological, structural and thermal properties, CO 2 pressure, impregnation time and G:Ch mass ratio were varied. Gelatin fraction in the films of 25-50 wt.%, scCO 2
... pressures of 10-20 MPa and impregnation time of 2-6 h impregnation favoured the CO loading. Processing of the film with equal gelatin to chitosan mass ratio (G/Ch 50:50 ) at 10 MPa for 2 h yielded sufficiently high loading (56 mg CO/g film ) without an adverse effect on morphological properties. The G/Ch 50:50 film was therefore chosen for structural and thermal analyses. ATR-FTIR analysis confirmed successful CO incorporation into the G/Ch 50:50 and its interaction with the film. Plasticizing effect of scCO 2 and CO on the film was evidenced by DSC. Incorporation of 56 mg CO/g film into the G/Ch 50:50 didn't affect thermal stability of the film. Beside environmental benefits, supercritical impregnation process enables fast fabrication of G/Ch bio-composite films containing CO, thermally stable to 110 °C, which is suitable for most of food packaging applications.