Superheated ethanol-water extraction

Another recently described methodology for the extraction of polyphenols is the use of superheated ethanol-water extraction (SEWE). This technique is a variation of SWE in which water-ethanol mixtures (20 80 or 40 60, v/v) are used in static extractions at high temperatures (180 C-240 C) and pressure (4 MPa). As for SWE, this method allows modification of the extract composition by changing the operation conditions (working pressure, temperature, and water/ethanol ratios). SEWE has been applied for the extraction of phenolic compounds from winery by-products with extraction efficiencies superior to those of conventional... 

Luque-Rodriguez JM, Perez-Juan P, Luque de Castro MD (2006) Extraction of polyphenols from vine shoots of Vitis vinifera by superheated ethanol- water mixtures. J Agric Food Chem 54 8775-8781... 

Luque-Rodrfguez, J.M., Pdrez-Juan, P., and Luque de Castro, M.D., Extraction of pol3q)henols from vine shoots of Vitis vinifera by superheated ethanol-water mixtures, J. Agric. Food Chem., 54, 8775, 2006. 

Finally, Luque-Rodriguez et al. [189] have studied the nonvolatile fraction of extracts from vine shoots obtained with superheated ethanol-water mixtures, a method which had previously proved effective for obtaining oak wood extracts [224,225]. The authors confirmed the superiority of PLE over conventional solvent extraction for this purpose showed that the extracts obtained with 80% (v/v) ethanol at pH 3.0 and 240°C for 60 min contained most of the compounds usually present in commercial wood extracts. 

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