PROBLEM TO BE SOLVED: To provide a method for producing a polysaccharide aqueous solution in which the reduction rate of viscosity upon hydrolysis on polysaccharide is extremely high and having no paste-like feeling after reduction of its viscosity, a polysaccharide aqueous solution obtained thereby, and a food product containing the polysaccharide aqueous solution.SOLUTION: Provided is a method for producing a polysaccharide aqueous solution containing a step where any one or more polysaccharide selected from alginic acid, sodium alginate, potassium alginate, ammonium alginate, propylene glycol alginate and carboxymethylcellulose and monovalent cations are dissolved into water to obtain a primary water solution and a step where the primary aqueous solution is subjected to heating treatment, and the polysaccharide dissolved into the primary water solution to obtain the secondary aqueous solution. In the primary water solution, the monovalent cation concentration is controlled to the range of 0.08 to 1.70 mol/L, the bivalent cation concentration is controlled to the range of 0.05 mol/L or lower, the pH is controlled to the range of 2.5 to 5.5, and the viscosity of the water solution is controlled to the range of 200 to 10,000 mPa s.SELECTED DRAWING: NoneCOPYRIGHT: (C)2016,JPO&INPIT【課題】多糖類を加水分解した場合の粘度低下率が極めて高く、粘度低下後に糊状感を有しない多糖類水溶液の製造方法、それによって得られた多糖類水溶液及び多糖類水溶液を含む食品を提供する。【解決手段】アルギン酸、アルギン酸ナトリウム、アルギン酸カリウム、アルギン酸アンモニウム、アルギン酸プロピレングリコールエステル及びカルボキシルメチルセルロースナトリウムのうちいずれか一以上の多糖類並びに1価カチオンを水に溶解して一次水溶液を得る工程と、該一次水溶液を加熱処理して、前記一次水溶液に溶解した多糖類を加水分解して二次水溶液を得る工程とを含む多糖類水溶液の製造方法であって、前記一次水溶液を、1価カチオン濃度が0.08~1.70mol/L、2価カチオン濃度が0.05mol/L以下、pHが2.5~5.5、水溶液粘度が200~10000mPa・sの範囲に調整する多糖類水溶液の製造方法である。【選択図】なし
