Extraction of ginger rhizome: partition constants and other equilibrium properties in organic solvents and in supercritical carbon dioxide

Abstract

Summary Equations have been derived for the direct and indirect methods of determining partition constants for constituents extracted from food and other natural materials. A careful distinction is drawn between mass and volume partition constants. The direct method has been applied to the extraction of [6]‐gingerol from Jamaican ginger rhizome with supercritical carbon dioxide and the indirect method to its extraction with acetone, dichloromethane, ethanol and isopropanol. The resulting average mass partition constants were 0.2 9 and 0.3 9 , respectively. The content of [6]‐gingerol in the original ginger rhizome was found to be 31–32μmol g −1 . The extent of oleoresin extraction from the ground ginger and the degree of swelling and organic solvent uptake were also measured.