Physicochemical quality and antioxidant activity of blackberry suspensions: Compositional and process effects

Abstract

The blackberry is characterized by its components presenting physiological activity. The objective of the research was to evaluate the influence of the composition and the homogenization time on the stability of suspensions based on blackberry concentrate (BC) and gum arabic (AG). The response surface methodology was used, considering the following independent variables: total solids provided by the BC TSBC (10%–11%), AG (0.4%–0.6%), and time (6–10 min), and the dependent variables: total suspension solids (TSS), pH, viscosity (μ), spectral absorption index (R), zeta potential (ζ), D10, D50, and D90, total phenols (TPs), antioxidant activity, and anthocyanins. The suspension was optimized under criteria of better physicochemical stability and higher antioxidant activity: TSS: 10.2 ± 0.2%, pH: 3.07 ± 0.01, μ: 1,123.7 ± 38.1 cP, R: 0.38 ± 0.04, |ζ|: 14.8 ± 0.9 mV, D10, D50, and D90 (6.6 ± 0.8; 86.7 ± 4.1, and 245.9 ± 12.9 μm, respectively), TP 473.5 ± 61.0 mg GAE/100g, DPPH and ABTS: 843.4 ± 66.7 and 699.9 ± 49.7 mg trolox/100g, respectively, and anthocyanins: 21.9 ± 1.6 mg cyd‐3‐glu/100g. The stability of the suspensions was favored by the synergistic effect of the μ‐ζ, the low values of particle size, and R. Practical applications Processing conditions and composition in the formulation of the suspensions based on blackberry, cause a series of changes in the quality parameters. The present work determines the stability of the colloidal system and composition in bioactive components, for effective use of the suspension in a spray drying process, thus strengthening the blackberry supply chain and generate value through alternatives that improve the shelf life of this fruit, characterized by having a short shelf life when they are in a fresh stage.

Refrigerated storage of blackberry cultivar ‘BRS Cainguá’ harvested at different ripeness stages

“…The physicochemical, morphological, and physiological characteristics of the blackberry make it very perishable, posing a challenge to overcome the barrier that it presents in relation to its shelf life, as it is very susceptible to mechanical damage and has a high respiratory rate (Soethe et Refrigerated storage of blackberry cultivar 'BRS Cainguá' harvested at different ripeness stages al., 2019;Carvajal et al, 2021). The use of techniques that increase the shelf life of fruits, without altering the physicochemical, sensory and nutritional characteristics, are of great importance to reduce post-harvest losses (Bersaneti et al, 2021).…”