Soluble dietary fiber from Canna edulis Ker by-product and its physicochemical properties

Using Canna edulis Ker by-product as raw materials, soluble dietary fiber (SDF) was prepared using six different methods, including chemical, physical–chemical, enzymatic, physical–enzymatic, chemical–enzymatic and physical–chemical–enzymatic methods. As main component in the C. edulis by-product composed of cellulose, glucose converts to other single sugars, which form a series of compounds in the SDF. The treated methods have impact effects on single sugar composition, metal ion content, molecular size distribution, chemical bonds and groups in the structure, thermal property and color of the final product. In view of security, high yield and homogeneity as well as good thermal stability of final product, physical–enzymatic method will be a best choice for the production of SDF from C. edulis by-product. The SDF obtained can be used as dietary supplement and additive in the food industry.