Release kinetics of lime essential oil (Citrus aurantifolia) from beads microencapsulated through ion-gel method

Abstract

Ca-Alginate beads for microencapsulation of lime oil (Citrus aurantifolia) by ion-gel method was manufactured and then soaked in Chitosan solution to obtain Ca-Alginate-Chitosan beads. Increased CaCl2 concentrations reduced lime essential oil release. The alginate concentration (2 to 3%) and water temperature significantly affected the release of oil (P < 0.05). The higher temperatures, the higher the release rate. The oil release at 75oC was twice as much as at 45oC. At 45oC, the difference in the release rate among the alginate concentrations of 2%, 2.5% and 3% was clear and statistically significant (P < 0.05). However, at 60oC and 75oC, there was no significant difference in release between the alginate concentration of 2.5% and 3% (P > 0.05). In the storage of beads in 1% CaCl2 solution at normal temperature, after the first 15 days, Ca Alginate-Chitosan system released about 3% slower than Ca-Alginate system, but there was no difference between the two systems after 45 days. This shows that if prolonged for a long time, the ion-gelation of Ca-Alginate prevails over the Alginate-Chitosan cross-link.