RT Journal Article
T1 Extraction of Antioxidants from Grape and Apple Pomace:Solvent Selection and Process Kinetics
A1 Garcia Montalvo, Jorge
A1 García Martín, Alberto
A1 Ibañez Bujan, Jon
A1 Santos Mazorra, Victoria Eugenia
A1 Yustos Cuesta, Pedro
A1 Bolívar Bolívar, Juan Manuel
A1 Ladero Galán, Miguel
AB Polyphenols have become a research target due to their antioxidant, anti-inflammatory and antimicrobial activity. Obtention via extraction from natural sources includes the revalorization of food wastes such as grape pomace (GP) or apple pomace (AP). In this work, GP and AP were submitted to a liquid–solid extraction using different solvents of industrial interest. Process kinetics were studied measuring the total phenolic content (TPC) and antioxidant capacity (AC), while the extraction liquor composition was analyzed employing chromatographic methods. Extraction processes using water-solvent mixtures stood out as the better options, with a particular preference for water 30%–ethanol 70% (v/v) at 90 °C, a mixture that quickly extracts up to 68.46 mg GAE/gds (Gallic Acid Equivalent per gram dry solid) and 122.67 TEAC/gds (TROLOX equivalent antioxidant capacity per gram dry solid) in case of GP, while ethylene water 10%–ethylene glycol 90% (v/v) at 70 °C allows to reach 27.19 mg GAE/gds and 27.45 TEAC/gds, in the case of AP. These extraction processes can be well-described by a second-order kinetic model that includes a solubility-related parameter for the first and fast-washing and two parameters for the slow mass transfer controlled second extraction phase. AP liquors were found to be rich in quercetin with different sugar moieties and GP extracts highlighted flavonols, cinnamic acids, and anthocyanins. Therefore, using identical extraction conditions for AP and GP and a comparative kinetic analysis of TPC and AC results for the first time, we concluded that ethanol/water mixtures are adequate solvents for polyphenols extraction due to their high efficiency and environmentally benign nature.
PB MDPI
SN 2076-3417
YR 2022
FD 2022
LK https://hdl.handle.net/20.500.14352/72308
UL https://hdl.handle.net/20.500.14352/72308
LA eng
NO Ministerio de Ciencia, Innovación
DS Docta Complutense
RD 17 sept 2024