摘要：Red grape pomace (RGP) and onion solid wastes (OSW) were used as raw material to produce flavonoid-enriched extracts, using ultrasound-assisted solid-liquid extraction. The extraction medium used was composed of water and glycerol and under the conditions used the extraction of flavonoids from both materials was shown to obey first-order kinetics. Maximum diffusivities (De) values were 4.01 × 10−11 and 2.35 × 10−11 m2·s−1, for RGP and OSW extraction, respectively, while the corresponding activation energies (Ea) were 14.00 and 15.23 kJ·mol−1.
