Soaking and grinding: Soak dehulled soybeans in water, then grind and cook the soaked beans.
Ethanol extraction: Use ethanol as a solvent to extract isoflavones from soybean flour.
Enzymatic hydrolysis: Use enzymes like β-glycosidase or tannase to convert isoflavone glycosides into aglycones.
N-hexane extraction: Extract soybeans with n-hexane, then dry and concentrate the extract
