METHODS
SHORTCUTS
ABOUT
FAQ
SUBSCRIBE
Methods Home
All Methods
Methods eXtras
Propose a Method
Cite a Method
Technical Committees
Archived Methods
Standards Affiliations
Suppliers Guide
Check Sample Program
Harmonized Methods
AACC International Approved Methods - AACC Method 20-20.01. Determination of Isoflavones in Soy and Selected Foods Containing Soy by Extraction, Saponification, and Liquid Chromatography

AACC International Approved Methods

Ingredients

AACCI Method 20-20.01
Determination of Isoflavones in Soy and Selected Foods Containing Soy by Extraction, Saponification, and Liquid Chromatography

VIEW METHOD

Objective
Test samples are extracted at 65° for 2 hr in 80% methanol solution and then saponified at ambient temperature with sodium hydroxide. The extracts are acidified, filtered, and diluted with water to 50% methanol. They are then centrifuged to clarify and are analyzed by liquid chromatography (LC). Isoflavone glucosides and aglucons are separated using a C-18 reverse-phase column with a methanol-water mobile phase and are measured by UV detection at 260 nm. Results are expressed in aglycon units by summing the concentrations of the aglycon isoflavones (genistein, glycitein, and daidzein) and the concentrations of the aglycon equivalents of the corresponding glucoside forms (genistin, glycitin, and daidzin).