Improvement in beta-carotene, vitamin B2, GABA, free amino acids and isoflavones in yellow and black soybeans upon germination

There is a lack of information on the various components in germinated soybeans. Therefore, this study aimed to further investigate the differences between three-day -germinated and raw (non-germinated) yellow and black soybeans. The results showed that germination increased the contents of beta-carotene and vitamin B2 significantly. The free amino acids in raw soybeans were not detected but determined in germinated soybeans, which illustrated that the total free amino acids in germinated soybeans were higher than in raw soybeans. Meanwhile, GABA was 10-fold increased in germinated soybeans. The increase of aglycones of isoflavones was significantly high that reached to over 700% in both soybeans. The total saponin content in germinated yellow soybeans was increased two times whereas there was a slight decline in germinated black soybeans. The anthocyanin content was found to be declined in germinated black soybeans. The current study indicates that three-day- germinated soybeans yield higher nutritional values than raw soybeans, suggesting that the germinated soybeans are a good source of various nutrients and other biologically active compounds.