Influencia de la composición del alimento y el proceso de secado por aspersión en la calidad de una mezcla de mora en polvo (Rubus glaucous Benth)

Abstract

The Castile blackberry (Rubus glaucus Benth) is a fruit rich in active components, which is framed within the context of functional foods, to provide well-being to the human being. The objective of the research was to evaluate the effect of the feed composition and the spray drying process (SD) on the quality of the blackberry powdered mixture (BPM). The response surface methodology was used with a central composite face-centered design (α=1), considering the following independent variables: inlet air temperature (IAT) (140 - 160 °C), outlet air temperature (OAT) (80 - 90 °C), atomizer disk speed (ADS) (20000 - 24000 rpm) and maltodextrin (MD) (5 – 9 %). The dependent variables were water activity (aw), humidity (Xw), solubility (S), wettability (We), hygroscopicity (H), angle of repose (AR), particle size (Span), total phenols (TP), antioxidant activity (ABTS and DPPH), anthocyanins (A), ellagic acid (EA) and product yield (Y). In general, We is the most critical variable in BPM, being statistically affected by most of the independent variables and by their linear and quadratic interactions. On the other hand, the experimental optimization of multiple responses defined the independent variables as IAT (159.3 °C), OAT (89.3 °C), ADS (24000 rpm), MD (5.5  %), and the dependent variables as aw (0.166±0.002), Xw (7.10±0.05 %), S (88.01±0.17 %), We (54.4±1.3 min), AR (7.4±3.7°), Span (1.69±1.04), TP (4513.1±23.5 mg AGE/100g dry base (db), ABTS (4012.7±34.0 mg TE/100g db), DPPH (5359.4±39.1 mg TE/100g db), A (281.2±29.4 mg C3G/100g db), EA (2653.0±155.0 mg/100g db) and Y (46.4±13.2 %). The spray drying (SD) process provides effective protection for the active compounds of the blackberry extract. In addition, it guarantees physicochemical stability for storage.