Simplified process of extraction of polyphenols from agroindustrial grape waste

Abstract The extraction, and stability of polyphenols from the grape residue were studied. extractions performed following Box-Behnken design, surface response methodology was used to model extraction total anthocyanins (TA), flavonols (TF), phenolics (TP). optimized simultaneously by desirability function. degradation kinetics monomeric anthocyanins, increase in polymeric color modeled under refrigeration conditions. with a temperature 60 °C, solid:liquid ratio 1/25 g/mL, time 80 min, maximized recovery TA (30.96 mg/100 g), TF (73.34 TP (856.78 mg EAG/100 g). followed kinetic first-order reaction, reaction rates (k) 4.10 x 10-3 days-1, 3.46 respectively. half-life (t1/2) 169 days. ethanol-citric acid solution allowed be efficiently extracted residue, had positive effect on anthocyanins.