Evaluation of mixtures of maltodextrin and gum Arabic for the encapsulation of Andean blueberry (Vaccinium meridionale) juice by freeze–drying

Abstract

SummaryAndean blueberry fruit is considered a source of bioactive compounds. However, its industrial applications as an ingredient are limited due to its low stability. In this work, Andean blueberry juice powders were obtained via freeze–drying. The effects of maltodextrin (MD) and gum Arabic (GA) as encapsulating agents were evaluated on the morphological, physicochemical, and rheological quality of the products, as well as in terms of the recovery of phenolic compounds. All the freeze–dried powders featured typical macroscopic and microscopic morphology, low moisture content (<5%) and water activity (aw < 0.3), high water solubility (>91%) and good flowability. The encapsulation with MD overall favoured higher water activity, solubility and flowability, and a significant increase of total phenolics recovery in the juice powders, compared with GA or GA:MD mixtures. The results showed that encapsulation by freeze–drying enables the production of Andean blueberry juice powders with suitable technological characteristics and potential as bioactive ingredients.