Effect of dynamic high pressure microfluidization modified insoluble dietary fiber on gelatinization and rheology of rice starch

Modification of insoluble dietary fiber (IDF) for facilitating its applications has been encouraged in food industry. IDF from soybean residues was treated by dynamic high pressure microfluidization (DHPM), and effect of modified IDF (MIDF) addition on gelatinization and rheology of rice starch (RS) was investigated. It was found that DHPM could effectively reduce particle size of IDF, induce puffed morphology, and increase their water holding capacity. Addition of IDF/MIDF to RS increased peak and final viscosity of paste, and MIDF decreased breakdown and setback value, indicating MIDF may be a great candidate for increasing stability of paste and restraining short-term retrogradation of starch gels. Dynamic rheology indicated that supplementing MIDF changed rheological properties of RS less than IDF did. The results suggested that DHPM would provide an opportunity to change the physicochemical properties of IDF, and the resulting MIDF may be more suitable for designing fiber-enriched products.