 The AA was dissolved in solutions of the wall material prior to processing . For the rice starch , gelatin was used as a binding agent and recovery was effected with calcium pectate . The morphology of the materials was analysed by optical and scanning electron microscopy , it thus being possible to verify the formation and evaluate the structural characteristics of the microcapsules . The capsules produced with gum arabic were smaller ( d00% = 0 . 0 microns ) and with a multimode particle size distribution , whilst uncovered starch capsules containing 0-0% gelatin presented a distribution mainly in the range of 0-00 microns . 