Evaluation of the fermentation properties of different soybean (Glycine max L.) cultivars

The enzymatic activity (EA) and amino-type nitrogen (ATN), viscous substance (VS), organic acid (OA), free amino acid (FAA) and volatile compound (VC) content in fermented soybeans of six cultivars (Glycine max L. ‘Taekwangkong ’[TKK], ‘Daechankong ’[DCK], ‘Misokong ’[MSK], ‘Seonpungkong ’[SPK], ‘Uramkong ’[URK] and ‘Chamolkong ’[COK]) were compared. Fermentation increased the quality indices such as EA, ATN and VS in soybean and their highest content were observed in DCK. The content of major OAs decreased in the following order: lactic acid > acetic acid > fumaric acid. The essential amino acid (EAA) content was increased by fermentation and FAA production had a positive effect on the abundance of the fermentation metabolites α-amino-n-butyric acid and ornithine. The content of the VS pyrazine differed with cultivar. Overall, soybean cultivars showed differences in the composition and fermentation properties, with raw DCK soybeans being particularly suitable for fermentation.