Microencapsulation of Orange Oil by Complex Coacervation and its Release Behavior (REASEARCH NOTE)

Microencapsulation of liquid orange oil as a common flavoring agent in food industries by complex coacervation in a gelatin – gum arabic polymeric wall system was studied. At a fixed ratio of 10% w/v as concentration of the materials used in this study, trend of changes of microencapsulation process variables using different wall polymeric contents along with varying levels of the core to wall ratio were investigated. Distribution pattern of the coacervate particle size showed that more than 70% of the particle with the average diameter of 9.68 mm were reasonably encapsulated in those treatments having core to wall ratio at the level of 1:1 and 1:2 while gelatin to gum arabic content of the wall system were set to be 1:1 and 2:1 ratio, respectively. The yield of the process as ratio of the amount of coacervate microcapsules produced to the amount of materials initially present in the emulsion was highest (69%) for the treatment described. Moreover, the release and swelling data have been analyzed in terms of the generalized equation Mt/M∞=ktn applicable for swellable controlled release systems. The results obtained were discussed on the basis of the release rate constant k, and diffusional exponent n.