As the protein by the fact that the function which is stabilized is granted, the new water soluble soybean polysaccharide is offered to the water soluble soybean polysaccharide in the pH limits near isoelectric point of the protein, it designated that it can disperse can be stabilized the protein in the pH limits near isoelectric point of the protein, it offers the new dispersed stabilizer and the acidic protein eating and drinking item which uses this as topic. By the fact that it builds a bridge the water soluble soybean polysaccharide which is obtained with the extraction of the soybean seed raw materials, in the pH limits near isoelectric point of the milk protein, it was possible to improve the dispersed stability of the protein. In addition, low it could obtain the acidic protein eating and drinking item of the viscosity which uses this water soluble soybean polysaccharide.水溶性大豆多糖類に蛋白質の等電点付近のpH域で蛋白質を安定化する機能を付与することで、新規な水溶性大豆多糖類を提供するとともに、蛋白質の等電点付近のpH域で蛋白質が分散安定化できる、新規な分散安定剤およびこれを用いた酸性蛋白飲食品を提供することを課題とした。大豆種子原料の抽出により得た水溶性大豆多糖類を架橋させることで、乳蛋白質の等電点付近のpH域における、蛋白質の分散安定性を向上させることが出来た。また、この水溶性大豆多糖類を用いた低粘度の酸性蛋白飲食品を得ることが出来た。
