Preparation and Properties of Anthocyanin Microcapsules from Passiflora edulis Rind by Complex Coacervation

In order to improve the stability of anthocyanin, microcapsules of Passiflora edulis rind anthocyanin were prepared by complex coacervation using gelatin and gum Arabic as wall materials. In this study, the embedding efficiency of anthocyanin microcapsules was optimized by the Box-Behnken design. Meanwhile, properties of anthocyanin microcapsules were studied by droplet size, moisture content, morphology and thermal stability. The results showed that the optimum conditions of anthocyanin microcapsules were the core/wall ratio 1:4.7, gelatin/gum Arabi ratio 6:7, the wall material concentration 1.5%, pH value 3.30, reaction temperature 40 ℃, reaction time 30 min and transglutaminase dosage 25 U/g gelatin. Under these conditions, the model was reliable and the embedding efficiency of microcapsules was 96.83%. The particle size, moisture content, and the melting temperature of anthocyanin microcapsules were 12.15 μm, 2.69%, and 82.51 ℃, respectively. Microcapsules presented spherical structures with smooth surfaces. The research provides some references for the application of Passiflora edulis rind anthocyanin.