The invention provides compositions and methods for isolating phenolic compounds, particularly isoflavones, from aqueous extracts of plant materials that contain such compounds. The process comprising: (a) providing an aqueous plant extract at a first pH less than 10, the aqueous plant extract comprising a plurality of phenolic compounds (b) extracting the aqueous plant extract with a first organic solvent to yield a first organic extract (c) extracting the first organic extract with an aqueous phase of pH greater than 10 to yield a phenol rich aqueous phase (d) adjusting the pH of the phenol rich aqueous phase to a pH of less than 9 and (e) isolating the phenolic compounds from the phenol rich aqueous phase.