Optimized aqueous extracts of maqui (Aristotelia chilensis) suitable for powder production

Abstract

The aim of this work was to obtain powders rich in bioactive compounds from maqui berry aqueous extracts by spray drying. First, the process parameters of the maqui aqueous extraction were optimized. The optimal operating conditions were found using an experimental Box-Behnken design with three factors: solvent/fruit ratio (2:1, 3.5:1 and 5:1), extraction temperature (25, 50 and 75°C) and extraction time (30, 75 and 120 min). Soluble solids content, monomeric anthocyanin content (ACY), total polyphenol content (TPC) and antioxidant capacity in the liquid extracts were analyzed as key responses to find the optimal extraction conditions. Secondly, the best aqueous extract (solvent/fruit ratio = 2:1; extraction temperature = 75°C and extraction time = 75 min) was subjected to spray drying. The effects of different drying adjuvants (maltodextrin, colloidal silicon dioxide, arabic gum, and microcrystalline cellulose) on the powders flow properties, the process yield (PY), the bioactive compounds content and the superficial color were studied. The product based on colloidal silicon dioxide presented the best powder properties: excellent flowability (a: 30.4 ± 0.7°, CI: 8.0 ± 1.7%), adequate moisture content (4.9 ± 0.3%), very good PY (70 ± 1%), high ACY (1528 ± 41 mg cy-3glu/100 g of powder) and TPC (3936 ± 132 mg GAE/ 100 g of powder), and a purple hue. This maqui powder offers valuable properties that allow its use, among other applications, as a functional ingredient, natural colorant and nutraceutical product.

New Freeze-Dried Andean Blueberry Juice Powders for Potential Application as Functional Food Ingredients: Effect of Maltodextrin on Bioactive and Morphological Features

“…In this sense, a high correlation (R 2 = 0,99) between the polyphenol content and the antioxidant activity of the powders was obtained, indicating a strong influence of the phenolic compound on this parameter. This correlation between polyphenol content and antioxidant capacity was also observed by Garrido-Makinistian et al [32] in maqui powders obtained by spray-drying.…”

Evaluation of Color, Texture, Sensory and Antioxidant Properties of Gels Composed of Freeze-Dried Maqui Berries and Agave Sugar

“…Freeze-dried powders of maqui berries obtained by Casati et al [36] were also characterized by a dark color. In other studies [37,38], maqui powders obtained from extract with spray drying exhibited a vivid purple color and were therefore much lighter than those obtained from whole berries using freeze-drying.…”

Membrane Technology for Valorization of Mango Peel Extracts

“…To prepare the aqueous extracts, mango peels were thawed in a refrigerator at 4 °C, weighed, and subjected to size reduction by milling, to homogenize and allow a better recovery during the extraction process as indicated by several authors [ 20 , 21 ]. Hot water was added to this preparation, at a temperature of 70 °C [ 29 , 30 ], keeping a solid-to-liquid ratio 1:10 (1 kg of fresh mango peel/10 L of water), because this proportion was considered the most suitable ratio to achieve a high extract yield and a reduced operating cost for these kind of samples [ 31 ]. The heating of aqueous extracts was carried out in a water bath with stirring, at an orbital speed of 1000 min −1 , for 75 min, a time considered optimum in the preparation of aqueous extracts from fruit bioresidues [ 29 ].…”

“…Hot water was added to this preparation, at a temperature of 70 °C [ 29 , 30 ], keeping a solid-to-liquid ratio 1:10 (1 kg of fresh mango peel/10 L of water), because this proportion was considered the most suitable ratio to achieve a high extract yield and a reduced operating cost for these kind of samples [ 31 ]. The heating of aqueous extracts was carried out in a water bath with stirring, at an orbital speed of 1000 min −1 , for 75 min, a time considered optimum in the preparation of aqueous extracts from fruit bioresidues [ 29 ]. The extracts obtained were then filtered through cotton cloths to separate the liquid and solid fractions.…”