Microencapsulation of cardamom essential oil with gum arabic, maltodextrin and inulin and the investigation of their physical-chemical properties

This study was aimed to microencapsulation of cardamom essential oil, to compare the effect of adding maltodextrin and inulin to gum arabic as a coating material and also to investigate the stability and properties of the produced microcapsules. In this study, gum Arabic, maltodextrin and inulin were used as wall compounds. The properties of the best composition containing the stability of microcapsules during nine weeks of storage in the testing medium, the microencapsulation efficiency determined by GC-MS, the mass and particle density, moisture, solubility, shape and particle size were investigated. The composition of gum arabic, maltodextrin and inulin with the ratio of 25:50:25 was considered as the best composition, based on the results of the microencapsulation efficiency, the release of cardamom essential oil in the simulated oral medium and powder recovery. The results showed that the stability of α-terpinyl acetate and 1,8-cineole were increased during nine weeks of storage at ambient temperature. The images of scanning electron microscopy showed that the best composition is spherical and has a slight crack. The microencapsulation efficiency of the active compounds including α-terpinyl acetate and 1,8-cineole were obtained 77.67% and 63.15%, respectively. Moisture content was 3.77%, the solubility was 87.56%, mass and particle density were from 0.41 to 0.32 g.mL-1, respectively, and the particle size was 2.5 μm and also particle size distribution 0.825. Also, the results showed that inulin has a high potential for the replacement of gum Arabic. The selected wall materials could be effectively used for the production of cardamom essential oil microcapsules with the microencapsulation efficiency maximum of cardamom essential oil, α-terpinyl acetate and 1,8-cineole, and the release of cardamom essential oil and powder recovery. In general, the results showed that using the best composition produced by spray drying can increase the stability and solubility of cardamom essential oil.