Isoflavones in Coffee

Abstract

Isoflavones are phenolic compounds that are structurally and functionally similar to 17ß-estradiol. They have weak estrogen-like effects and antioxidant activity. Coffee beverages could be an interesting source of these compounds, especially in populations where they are moderately consumed. Several methods for total isoflavone quantification in coffee are described in the literature. A common feature is the use of hydrolysis (enzymatic or acid), either combined or not with a direct extraction with a solvent and/or a solid-phase extraction step, followed by chromatographic analysis. Coffee species influence the isoflavone content in coffee beverages. Robusta beans contain higher levels of isoflavones (especially formononetin) than arabica ones. During roasting, isoflavone content decreases 30-40% (from a light to dark degree). Simultaneously, the compounds' extractability increases.