Microencapsulation of Bioactive Compounds from Hibiscus Calyces Using Different Encapsulating Materials

Abstract

Abstract: Hibiscus calyces extract was microencapsulated by freeze drying and spray drying using partially hydrolyzed guar gum (PHGG), polydextrose (PD) or gum Arabic (GA) at 10 % as encapsulating agents. The retention of anthocyanins ranged from 59.8 to 64.6 % and from 66.4 to 74.3 %, and for antioxidant activity from 66.54 to 71.71 and 69.90 to 73.26 %, for spray-dried and for freeze-dried powders, respectively. The best result obtained, for the anthocyanins content, reducing capacity and ABTS, was for the powder produced by freeze drying using GA. Regarding physical powder properties, samples produced by spray drying using GA, followed by PHGG had the best results, with values of 95.80 and 95.20 %, 31.33 and 28.87 %, 17.43 and 10.96°C for solubility, hygroscopicity and Tg, respectively. Microscopy analysis also indicated that powders produced by spray drying using GA and PHGG had the best structures, showing particles of spherical shape and without agglomeration.