| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 230650 | The Journal of Supercritical Fluids | 2014 | 8 Pages |
•Grape marc by-product of wine industry as source of phenols of added value.•Phenols extraction by SFE using SCCO2 modified with water (W) and ethanol (EtOH).•Determination and discussion of SFE overall extraction curves (OECs).•Operating conditions selected: SCCO2 + 15% W/10 MPa/313.15 K; SCCO2 + 15% EtOH/10 MPa/333.15 K.•Combining SCCO2 + 15% W and SCCO2 + 15% EtOH: obtained 68 g phenols/kg of extract.
Supercritical carbon dioxide (SC-CO2) extraction of grape marc was studied using water (W) and ethanol (EtOH) as co-solvent at 15% (w/w), 100 and 200 MPa, and 313.15, 323.15 and 333.15 K to analyze their influence upon total phenols of the extracts. The overall extraction curves were determined and suggested 10 MPa and 313.15 K as the best operating conditions for SC-CO2 + 15%W extraction, and 10 MPa and 333.15 K for SC-CO2 + 15% EtOH. The phenolic yields obtained were 63.4 g/kg of extract for SC-CO2 + 15% W and 38.8 g/kg of extract for SC-CO2 + 15% EtOH. An alternative method combining Sc-CO2 + 15% W extraction, followed by SC-CO2 + 15% EtOH was tested. This procedure provided the best results allowing to obtain the highest phenolic yield (68.0 g/kg of extract), phenol content (733.6 mg GAE/100 g DM), proanthocyanidins concentration (572.8 mg catechin/100 g DM) and antioxidant activity (2649.6 mg α-tocopherol/100 g DM). SC-CO2 methods were compared with methanol extraction.
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