The germination of soybeans increases the water-soluble components and could generate innovations in soy-based foods

Abstract

Changes in the aqueous solubility of proteins, amino acids, sugars, and other bioactive compounds of the soybean (BRS 257) were studied after different germination times (0, 8, 32, 56, 80, 104 and 176 h). The germination process clearly changed the solubilization of the components, and even antioxidant activities, in aqueous extracts. Significantly (p < 0.05) the highest protein extraction yield occurred after 80 h of germination. Except for time zero, most of the protein has already been extracted in the first of the 3 extraction cycles performed. A variation in the concentration of amino acid residues was observed throughout germination. A significant increase in digestibility occurred initially at 32 h reaching its maximum with 176 h. After 32 h there was a significant increase in sugar solubility, and the total phenolic and flavonoids concentrations it was 4 and 2.5 times higher than the nongerminated grain extract, respectively. The maximum antioxidant capacity was also reached with 32 h of germination. In general, the germination time of 32 h presented outstanding results but the first changes were already detected after the first 8 h. The data demonstrate the usefulness of germination for innovations in soy-based food production with better nutritional and nutraceutical values.