Spray-dried powders from berries extracts obtained upon several processing steps to improve the bioactive components content. AbstractThis work aimed at developing powders rich in antioxidant compounds and pigments from three berries grown in argentine Patagonia: blackcurrant, raspberry and elderberry. Ultrasound-assisted extraction (UAE) was applied on the precipitates generated after juice production in order to improve bioactive compounds recovery. The best extracts (UAE 10 min for raspberry and blackcurrant, and 5 min for elderberry), obtained after 2-3 extraction cycles were mixed and spray-dried. The glass transition temperatures (43-50°C), and the low water content (0.92-1.44 %) and water activity values (<0.06) of the powders suggest that they could be stored at room temperature without risk of physical deterioration. Elderberry and blackcurrant powders showed good flowability and low cohesiveness while raspberry powders presented an intermediate cohesiveness and fair flowability. This was consistent with the smooth surface and the less shrinkage of the raspberry powder particles observed by microscopy. Elderberry powders presented higher concentration of bioactive compounds (polyphenols content 4.57±0.23 mg gallic acid (GA)/g d.m. and monomeric anthocyanins content 2.39±0.12 mg cyd-3-glu/g d.m.), and higher antioxidant capacity (3.33±0.57mg GA/ g d.m.) when compared to raspberry and blackcurrant. The obtained powders result possible ingredients to be used as natural colorants or antioxidants.

Blackcurrants contain high levels of polyphenolics, particularly flavonols and anthocyanins, which contribute to their high antioxidant activity. The aims of this work were the recovery of bioactive compounds from the remaining solid (waste) after processing blackcurrant juice and to obtain spray-dried powders from the blackcurrant juice and extracts. The extraction of bioactive compounds from the fruit pulp was performed by ultrasound-assisted extraction. Experiments were conducted to select the more suitable solvent, and citric acid was chosen. Then, to optimize the extraction conditions (time, solvent concentration, and amplitude) an experimental design using a Box-Behnken Design was done. Comparing the optimized extract with the fruit, 31% total monomeric anthocyanins, 19% total phenolic compounds, and 10% antioxidant capacity were obtained. The optimized extract and the juice were mixed and spray dried, using maltodextrin as carrier matrix. A blackcurrant powder with low hygroscopicity 14.46 ± 0.13 (g a.w./100 g d.m) and high solubility 94.25 ± 4% was obtained. High concentration of bioactive compounds and antioxidant capacity was recorded: Total monomeric anthocyanins 63.01 ± 1 (mg cyn-3-glu/100 g.d.m), total phenolic content 116.87 ± 5 (mg gallic acid/100 g d.m.), and antioxidant capacity 144.40 ± 0.11 (mg eq Trolox/100 g.d.m.).

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