Table 2.
Overview of the most relevant green extraction methods and related optimal extraction conditions for CGAs recovery from agri-food waste.
| Source | Type of Waste | Extraction Method |
Optimal Extraction Conditions |
Ref. |
|---|---|---|---|---|
| Coffee | Husk | UAE | 50% EtOH, 35 °C, 1 h, 1:10 w/v, 40 kHz, 220V |
[23] |
| CSE | 50% EtOH, 60 °C, 1 h, 1:10 w/v |
[23] | ||
| Spent ground | CSE | 15–20% EtOH, 40–60 °C, 15–25 min, 0.30:25 w/v |
[42] | |
| UAE | 100% EtOH, 40 °C, 34 min, 1:17 w/v, 20 KHz, 244 W |
[43] | ||
| UAE | betaine:triethylene glycol 1:2, 30% water, 65 °C, 20 min, 1:15 w/v, 37 KHz, 200 W |
[21] | ||
| Silverskin | MAE | 60% EtOH, 43.5 °C, 31.5 min, 1:35 w/v, 280 W |
[24] | |
| CSE | 60% EtOH, 67.5 °C, 36.5 min, 1:35 w/v |
[24] | ||
| Artichoke | Bracts, stems | CSE | 80% EtOH, 60 ± 0.1 °C, 60 min, 0.5:15 w/v | [30] |
| Leaves, external bracts, stalks, receptacles | MAE | 50% EtOH, 50–69 °C, 3 min, 0.3:10 w/v, 900 W |
[45] | |
| Internal and external bracts | UAE | 75% EtOH, 25 °C, 10 min, 1:10 w/v, 20 kHz, 240 W |
[46] | |
| Outer bracts, stems | UAE | 100% water, 60 min, 1:3 w/v, 25 kHz, 1200 W, 50 W/L | [28] | |
| Bracts, leaves | PHWE | 10% EtOH, 93 °C, static time 5 min, 2 cycles, 103 bar | [29] | |
| Tomato | Peel | MAE | 70% EtOH, 55 °C, 5 min, 1: 50 w/v, 0–500 W |
[37] |
| Potato | Peel | MAE | 60% EtOH, 80 °C, 2 min, 1:40 w/v, 300 W, 120 rpm magnetic stirring |
[47] |
| UAE | 83% glycerol, 80 °C, 90 min, 1:81 w/v, 37 kHz, 140 W, 35 W/L |
[67] | ||
| SCW | 100% water, 160 °C, 60 min, 60 bar, 2 mL/min |
[49] | ||
| Walnut | Leaves | MAE | 100% water, 61.1 °C, 3 min, 0.030:1 w/v, 850 W, 600 rpm magnetic stirring |
[35] |
| CSE | 100% water, 29.9 °C, 150 min, 0.030:1 w/v, 600 rpm magnetic stirring |
[35] | ||
| Blueberry | Leaves | MAE | 30% EtOH+ 0.03% citric acid (1.5 M), 4 min, 0.5:80 w/v, 141.1 W | [31] |
| Cocoa | Bean shell | MAE | 100% water, pH 12, 97 °C, 5 min, 0.04:1 w/v, 500 W, 400 rpm magnetic stirring | [51] |
| Sunflower | By-products | MAE | 70% EtOH, 200 W, 30 s, 1:10 w/v | [53] |
| Citrus | Peel | CSE | 80% EtOH, 40 °C, 20 h, 1:15 w/v | [52] |
| UAE | 80% EtOH, 45 °C, 60 min, 1:20 w/v, 35 kHz | [52] | ||
| Cauliflower | External leaves, stems | CSE | 100% water, 70 °C, 20 min, 1:1 w/w | [58] |
| MAE | 100% water, 4 min, 1:1 w/w, 750 W | [58] | ||
| Celery | External leaves, stems | CSE | 100% water, 70 °C, 20 min, 1:2 w/w | [58] |
| MAE | 100% water, 4 min, 1:2 w/w, 750 W | [58] | ||
| Tobacco | Midrib, dust, scrap | UAE | 40–55.43% EtOH, 30.14–53.59 °C, 15.19–30.31 min 1:10–11 w/v, 37 kHz, 50 W | [54] |
| Carrot | Pomace | UAE | 80% EtOH, 20 °C, 10 min, 1:50 w/v, 20 kHz, 70% amplitude level, 48 W/cm2 | [33] |
| Almond | Skin | UAE | 50% PEG200, 75 °C, 20 min, 1:20 w/v, 40 kHz, 120W | [32] |
| Apple | Pomace | PLE | 100% water, 60 °C, 60 min, 100 bar, 2 mL/min | [57] |
| Olive | Tree biomass | SFE | CO2+ 60% EtOH, 50°C, 60 min, 1:3 w/v, 300 bar | [56] |