Hydrothermal treatments in the development of isoflavone aglycones in soybean (Glycine max (L.) Merrill) grains

Studies were carried out to enhance the development of isoflavone aglycones in soybean. Grains of two soybean cultivars, BR 36 mid IAS 5, 115 mid 278 mg1100g of total isoflal'017e, respectively, ivere treated hYdrotherinal.yl at 45, 60 and 85 degreesC for 5, 30 and 60 minutes. Pre-treatments of grains at 60 degreesC for 60 minutes allowed a considerable increase of the isoflavone aglycones. Non-treated grains of BR 36 and IAS 5 showed 1.2 mg/100g of genistein, after hydrothermal treatments, which increased to 12 and 53 mg/100g, in each variety, respectively. At higher temperature (85 degreesC) there was a decrease of the aglycones due to inactivation of beta-glycosidases. Malonyl compounds were also reduced at higher temperatures. In processing functional soybeam foods, hydrothermal treatments of the soybeam grains, as well as high isoflavone content soybean cultivars will enhance development of aglycone forms.