Disclosed is a composition for supplying dietary fiber to food and drink and/or for improving quality of food and drink, which includes a partially hydrolyzed substance of glucomannan. This partially hydrolyzed substance of glucomannan has a viscosity in a 1% aqueous solution which is in a range of 1,000 to 10,000 mPa·s and a weight average molecular weight which is in a range of 100,000 to 800,000. Because an aqueous solution thereof is lowly viscous, not only the composition can be added to food and drink, in a comparatively high concentration, but also upon adding the composition to an emulsified food such as an ice cream, even by heating, a shape of the food before heating can be retained.
