Bioactive compounds-rich powders: Influence of different carriers and drying techniques on the chemical stability of the Hibiscus acetosella extract

The effects of different drying methods (freeze- and spray-drying) and carriers (gum Arabic and inulin) on the powder characterization and stability of the bioactive compounds of Hibiscus acetosella extract (HAE) during storage were evaluated. The H-1 NMR spectrum of the HAE revealed characteristic signals of the caffeoyl hydroxycitric acid. The encapsulated extract powder presented different morphology according to the drying processes. The powders produced by the freeze-drying process presented higher retention of bioactive compounds due to the low temperature process. The mixture of gum Arabic and inulin as carrier resulted in the absorption of larger amount of water. The half-life time of the encapsulated extract powders ranged from 31 to 36 h (DPPH) and from 34 to 71 h (phenolic compounds). In general, the powders constituted of gum Arabic and recovered by the freeze-drying process presented better protection and retention of the bioactive compounds from the HAE. (C) 2019 Elsevier B.V. All rights reserved.