Table 1.

Phenolic extraction from wine lees samples.

Sample	Pre-Treatment	Solvents	Extraction Mode	Reference
Wine lees from red grapes (Vitis vinifera cv. Syrah).	Lees were centrifuged at 2100× g and the solid phase was dried at 40 °C for 48 h in an oven, milled, and sieved (particle size: 0.5 mm).	The lees were mixed with ethanol 75% (hydrochloric acid 1% in water) in a 1:10 (w/v) ratio.	(1) A microwave-assisted extraction at 200 W irradiation power for 17 min was applied. (2) The mixture was stirred at 40 °C for 24 h.	[24]
Wine lees from red grapes (Vitis labrusca hybrid varieties: BRS Violeta and BRS Lorena).	Lees were freeze-dried for 48 h.	A sample of 0.25 g was extracted with 50 mL of methanol/water/formic acid (50:48.5:1.5, v/v/v).	The mixture was placed in ultrasonic bath during 2 min and centrifuged at 5000× g at 5 °C for 5 min.	[2]
Wine lees from red grapes (mixture of Vitis vinifera cv. Cabernet Sauvignon 60%, Merlot 30%, and Cabernet Franc 10%).	Wine lees were dried in an oven at 40 °C for 48 h, and then milled and sieved (particle size: smaller than 0.6 mm).	Dried wine lees and 50 mL of aqueous ethanol solution were mixed.	(1) The mixture was placed in an ultrasonic bath system and centrifuged at 12,000 rpm for 10 min. (2) Conventional solvent extraction: maceration.	[19]
Wine lees from red grapes (variety not mentioned).	Lees were dried in a climate chamber at 40 °C, ground, and sieved (particle size: 100–300 µm).	A sample of 1 g was extracted with 25 mL ethanol/water (1:1).	The mixture was placed in an ultrasound bath.	[23]
Wine lees from red grapes (Vitis vinifera cv. Tempranillo, Merlot, Garnacha, Cabernet, and Mazuelo).	Lees were centrifuged at 855× g and the solid phase was dried at 40 °C for 48 h in an oven, milled, and sieved (particle size: 0.5 mm).	A sample of 6 g was mixed with 50 mL of 60:40 (v/v) ethanol-water (adjusted to pH 4 with formic acid).	The mixture was placed in a microwave-assisted digestor at 140 W irradiation power for 10 min.	[25]
Wine lees from white grapes (Vitis labrusca cv. Niagara).	Lees were freeze-dried.	A sample of 1 g was homogenized with 3 mL of pure water.	The mixture was agitated at 150 rpm overnight at room temperature.	[15]
Wine lees from red grapes (Vitis vinifera cv. Pinot noir).	Lees were dried in an air-circulation oven for 12 h at 50 °C and ground.	A sample of 20 g was homogenized with 150 mL of ethanol/water/formic acid (50:48.5:1.5, v/v).	The mixture was placed in a blender for 2 min and centrifuged at 2500× g for 15 min.	[28]
Wine lees from red grapes (Vitis vinifera cv. Merlot).	Lees were lyophilized.	(1) NADES: mixtures of choline chloride with a hydrogen donor. (2) Ethanol/water/formic acid (50:48.5:1.5, v/v/v) at pH 2.7.	The mixtures were placed in an ultrasonic bath system with different time and ultrasonic power depending on an experimental design.	[26]
Aging wine lees from red grapes (Vitis vinifera cv. Tempranillo).	Lees were centrifuged for 90 min at 10,000 rpm and were freeze-dried for 48 h.	A sample of 0.25 g was mixed in 10 mL of solvent: distilled water, ethanol, acetone, methanol and two mixtures of ethanol:water (50:50 and 75:25 v/v).	The mixture was stirred for 5 min at room temperature followed by 10 min of sonication in an Transsonic 700/H bath.	[9]