PROBLEM TO BE SOLVED: To provide a novel water-soluble dietary fiber that can improve the taste of food and drink.SOLUTION: An indigestible glucan is composed of a thermal condensate of a starch decomposition product with a DE of 70-100, where the indigestible glucan has a dietary fiber content of 30-65 mass% and a weight average molecular weight of 700-1250. There are also provided a carbohydrate decomposition enzyme treatment product of the indigestible glucan, and a fractionation treatment product thereof.SELECTED DRAWING: NoneCOPYRIGHT: (C)2019,JPO&INPIT【課題】飲食品の呈味を向上させることができる新規な水溶性食物繊維の提供。【解決手段】本発明によれば、DE70~100の澱粉分解物の加熱縮合物からなる難消化性グルカンであって、食物繊維含量が30~65質量%であり、かつ、重量平均分子量が700~1250である、難消化性グルカンおよびその糖質分解酵素処理物並びにそれらの分画処理物が提供される。【選択図】なし