Search Results (2)

Agro-industrial wastes can be used to obtain high-value compounds rich in antioxidant and antimicrobial activity. This study aimed to compare different extraction techniques for the recovery of sugars, antioxidants, and antimicrobial compounds from brewer’s spent grain (BSG), blue agave bagasse (BAB), spoiled blackberries (BB), and raspberries (RB). Aqueous (AQ), enzymatic (E), chemical-enzymatic (CE), and hydroalcoholic (EOH) extractions were assessed, and sugars, phenolics, flavonoids, and anthocyanin contents were quantified. Antioxidant activity of the extracts was evaluated using the ABTS and DPPH assays, and antimicrobial activity was tested against three yeasts and six bacteria. The CE process gave the highest total and reducing sugars content for the four residues tested, and the highest antioxidant activity, phenolics, flavonoids and anthocyanin content for BAB and BSG. Regarding BB and RB, the best treatment to obtain total and reducing sugars and antioxidant activity with ABTS was CE; the highest content of anthocyanins, phenolic, flavonoids and antioxidant activity with DPPH was obtained with EOH treatment. CE extracts of BSG and RB showed the highest inhibition against the strains studied. Results show that BSG, BB, and RB can be a source of antioxidants and antimicrobial compounds for the food and pharmaceutical industries. Depending on the desired application and component of interest, one of the extraction techniques evaluated here could be used. Full article

The process of drying food is necessary to preserve it; however, some bioactive compounds can be degraded during drying process. In this work, the convective drying process of Peruvian blackberry bagasse and the degradation of anthocyanins, total phenolic content (TPC), and antioxidant capacity (AC) were studied. The logarithmic model fitted well to the data and could predict the process, showing that 6 h of drying at 90 °C is enough to reach equilibrium moisture. Anthocyanin degradation followed a first-order kinetic model with reaction rate constant between 5.45 × 10⁻² ± 4.68 × 10⁻³ and 1.21 × 10⁻¹ ± 2.31 × 10⁻² h⁻¹, and activation energy of 25.11 kJ/mol. The highest retention (84.38%) of anthocyanins was obtained in 1 h at 50 °C and the highest degradation (68.54%) in 6 h at 90 °C. The TPC and AC increased with the drying time and temperature due to the increased water evaporation. Full article