Effects of ultra-fine micronization on the structure, rheological and functional properties of dietary fiber from Laminaria ja-ponica

Laminaria japonica is known to be a rich source of dietary fiber (DF). The DF in L. japonica was extracted by combined enzymatic and chemical method in this study. The effect of ultra-fine pulverization on structural and functional properties of DF fractions were also investigated. The results displayed that the molecular weight  of DF was 2.22 × 107 Da. After ultra-fine grinding, the viscosity of soluble dietary fiber (SDF) suspension increased from 4.65 ± 0.08 to 6.89 ± 0.24 mPa·s. In addition, ultra-fine grinding significantly reduced the particle size of DF with higher insoluble dietary fiber (IDF) yields. L. japonica IDF exhibited significant enhancement on absorption capacities of nitrite ion absorption, cholesterol and glucose, which could be utilized as potential ingredients in several DF intensified foods. This work could provide understanding into the influence of micronization on the structure-function relationship of food materials rich in dietary fiber.