Water-soluble dietary fiber-containing composition and method for preparing same

A water-soluble dietary fiber-containing composition comprises a water-soluble dietary fiber material and a thickening polysaccharide in a mixing ratio, by mass, ranging from 95:5 to 80:20 and has a solubility, in water at 30° C., of not more than 80%. The composition may be prepared by a method comprising the steps of dissolving, in water, a water-soluble dietary fiber material and a thickening polysaccharide such that the mixing ratio of the former to the latter, by mass, ranges from 95:5 to 80:20 and then drying the resulting aqueous solution. The composition has a low solubility in water and therefore, can be incorporated into various foods, while maintaining desired excellent quality thereof without being accompanied by the reduction of the working characteristics of the raw materials for these foods.