Abstract: This paper focuses on the physicochemical and functional properties of soybean dietary fiber from enzyme-assisted aqueous extraction processing (EAEP) and on its effect on the farinograph properties of wheat flour and the texture of dough as well as its effect in improving the texture and digestibility of biscuits. The results showed that the purity of the dietary fiber was 81.34%, and that the content of soluble dietary fiber accounted for about 50.83% of the total dietary fiber. The farinograph properties of wheat flour and the textural properties of dough were the best when added with the dietary fiber at 30%. The textural properties of the resulting biscuits were better than those of commercial high-fiber biscuits. Additionally, the digestion rate was significantly lower than that of commercial high-fiber biscuits and ordinary biscuits, accompanied by a decrease in rapidly digestible starch content by 17.14% and 42.57% and an increase in slowly digestible starch content by 24.93% and 110.27% as well as in resistant starch content by 0.85% and 21.57%, respectively, and the glycemic index was only 45.99, a value for low-sugar foods. Therefore, the dietary fiber had good physicochemical and functional properties, indicating its great potential in the baked food industry as a new resource of soybean dietary fiber.

Key words: soybean dietary fiber from enzyme-assisted aqueous extraction processing, biscuits, farinograph properties, texture properties, in vitro digestibility