Antioxidative Activity of Douchi (A Chinese Traditional Salt-Fermented Soybean Food) Extracts During Its Processing

Salt-fermented soybean foods are popular in Asia as an alternative food seasoning material. The α,α-Diphenyl-β-pricrylhydrazyl (DPPH) radical-scavenging activity, 2,2′-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical-scavenging activity and reducing power of the 50% ethanol extracts from one variety called in layman term as douchi were evaluated in this study. TEAC on DPPH radical and ABTS radical of extracts and the reducing powers of the extracts was found to increase significantly during the prefermentation (p 0.05). The results showed that the antioxidative compounds released during the douchi fermentation were inhibited by the high salt addition.