Effect of soybean cultivars on the content of isoflavones in soymilk
The aim was to study the relationship between the isoflavone content in different soybean cultivars and in the soymilk. Seven cultivars of soybean seeds from two locations with different levels of isoflavones were processed to soymilk. The content of total and individual isoflavones was determined by high performance liquid chromatography. The total phenolic content, oil and protein content in soybean cultivars were also determined. Significant differences in the content of individual isoflavones were observed within the soybean cultivars. The strong positive correlations were observed between total isoflavone content in soybean seeds and in soymilk. The total phenolic content in soybean cultivars ranged from 83 to 143.4 mg GAE/100g of soybean. The total isoflavone content in soybean seeds ranged from 71.2 to 133.8 mg/100g of soybean which comprise from 76.7 to 98.8% of the total phenols. In soymilks, total isoflavone content ranged from 16.1 to 61.0 mg/kg of soymilk. The most abundant isoflavone in soybean seeds was genistein while in soymilk it was genistin. There was statistically significant difference (p < 0.05) among two locations in total and individual isoflavone contents.