Effects of steam explosion on physicochemical, functional and structural properties of soluble dietary fiber from pomelo peel

The effects of steam explosion (SE) on the physicochemical, functional and structural characteristics of soluble dietary fiber (SDF) extracted from pomelo peel were evaluated. At the treatment condition of 0.9 MPa,120 s, the extraction yield of SDF increased by 156.7 %, and the water holding capacity, oil holding capacity, and swelling capacity increased by 36.6 %, 42.7 %, and 21.4 %, respectively. Additionally, in vitro hypoglycemic capacity, cation exchange capacity, nitrite ion adsorption capacity, and antioxidant capacity were all improved. It was observed that a large number of cracks in the SDF, and the structure of SDF became loose and porous and specific surface area of SDF increased to 1.41 times. In addition, the results from differential scanning calorimetry indicated that SDF treated with SE had better thermal stability, and the degradation temperature increased from 311.93 ? to 316.28 ?. So, SE could be used as an effective method for modifying dietary fiber.