Abstract: The research on preparation of nano dietary fiber by Microfluidizer homogenizer, and characteristics of T nano dietary fiber, such as surface areas, expansion ratio, water-retaining capability. The results show that the optimal homogenization pressure is 90MPa; surface area is 1.8189m2/g, and it is twice higher than normal fiber; and expansion ratio is 15.3265g/g, water-retaining capability is 21.5017g/g, both of them were three times higher than normal fiber.

Key words: nano dietary fiber, granularity, surface area, expansion ratio, water-retaining capability