Microencapsulation By Spray Drying From An Extract Of The Calyces Of Hibiscus Sabdariffa L.

The objective of the research was to define the best conditions for ultrasound-assisted extraction of H. sabdariffa L. calyces, and to obtain microencapsulated powders, by spray drying. The extracts were analyzed, considering as variables: extracting solvent (water and water/ethanol) and the temperature /extraction time ratio (25 degrees C/60 min and 60 degrees C/30 min). Inlet airtemperature (150 degrees C; 190 degrees C) and the mixture of gum a rabic (G) and maltodextrin (MD) as encapsulating agents (G40/MD60; G60/MD40) were the variables studied. The parameters used for the analysis were: yield, pH, degrees Bx, chemical composition (phenols and total anthocyanins, HPLC-MS), and antioxidant capacity (DPPH). The best polyphenols extraction conditions were water:ethanol (80:20), at 60 degrees C for 30 min. The presence of phenolic acids, flavonol glycosides, and a nthocyanins (delphinidin-3-sambubioside and cyanidin-3sambubioside) were identified as the signals of highest intensity. Inlet air temperature at 150 degrees C and G60/MD40 allowed the highest total phenols and a nthocyanins content. However, the antioxidant capacity was better at 150 degrees C and G40/MD60. The microparticle obtained could be used as an ingredient for the preparation of phytopharmaceuticals or functional foods, considering their easy handling, and antioxidant capacity.