RESUMEN
The effect of different polysaccharides combinations on the stability of maqui extract was studied in order to design functional foods, dietary supplements or natural colorants. Encapsulation by freeze-drying using maltodextrin, gum Arabic and inulin at 10, 20 and 30% was performed and phenolics, anthocyanin, antioxidant capacity and color difference of the microcapsules were determined. The stability of the bioactives after 60 days storage at 25 °C was also evaluated, along with analysis of aw, adsorption isotherm, and microstructure to characterize the powders. 10% encapsulating polysaccharide produced best results, with maltodextrin leading to highest process efficiency, while the mixture of maltodextrin/inulin in equal proportion led to highest retention of polyphenols (91.1%) and anthocyanin (98.8%) during storage. The inulin microcapsules retained 94.1% of its antioxidant capacity compared to 25.3% for the freeze-dried maqui powder. Concentration level and polysaccharide matrix of encapsulating agent significantly affect retention of bioactives in the microcapsules.
