Spray-dried Encapsulation of Roselle (Hibiscus Sabdariffa) and Evaluation of Their Potential as Rich-antioxidant Compound

Abstract

There is a growing demand using rich-antioxidant compounds from plant extract to develop functional food products or biomedical products. In this work, we studied the impact of producing encapsulated roselle extracts with 1% w/v microencapsulated carrier as a powder rich in antioxidant properties. In particular, the roselle extract was subjected to spray drying using an acidified solution as a solvent. Combinations between maltodextrin and xanthan gum as wall materials were first tried for the roselle. Characterization of the spray-drying powder was confirmed by scanning electron microscopy (SEM), titratable acidity, anthocyanin content, and antibacterial and antioxidant activities. The results showed the addition of xanthan gum directly affects the morphology and antioxidant activities of the encapsulated materials. The particles presented a spherical shape with diameters ranging from 3 – 5 µm.  The reduction of antioxidant activities and solubility were observed following the increasing concentration of xanthan gum. Thus, findings in this study have demonstrated that the obtained roselle spray drying powders can possibly be used as rich-antioxidant supplements for food, biomedical, and cosmetic industries.