Process for preparing highly water soluble double salts of hydroxycitric acid particularly alkali and alkaline earth metal double salts

This invention relates to a novel process for preparing highly water soluble alkaline earth metal and alkali metal double salts of hydroxycitric acid. These salts are practically odourless and has negligible taste and are therefor useful as nutraceuticals. Aqueous extract of the fruits belonging to Garcinia species are treated to precipitate its alkaline earth metal salts such as the calcium salt. This sparingly soluble product is dissolved in alkali hydroxide and the pH of the solution is adjusted by adding purified extract of the fruit rind. Ca/Na or Ca/K double salts are particularly useful.