| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high Ca-solubilization coefficient by reacting only an α-amylase on a phosphoric acid-bonding starch to form an oligosaccharide composition. SOLUTION: Slurry of a starch having a concentration of 30-50 wt.% is prepared and to this slurry is added 0.5-240 wt.%, based on the starch, of phosphoric acid and/or sodium phosphate, potassium phosphate or the like, followed by addition of an acid or an alkali to adjust pH. The slurry is dried until the water content becomes not more than 10 wt.% and then roasted at 100-250 deg.C for 5 minutes to 4 hours to prepare a phosphoric acid-bonding starch. The phosphoric acid-bonding starch is then made into slurry having a concentration of 10-40 wt.% and the pH of the slurry is adjusted at 6.0-6.3 by addition of a calcium hydroxide. Next, 0.001-0.5 wt.% of a heat resistant liquid type α-amylase is added to the slurry and the mixture is treated under a pressure at 100-110 deg.C for 2-15 minutes and decomposed by an enzyme at 90-100 deg.C for 30 minutes to 5 hours to produce a phosphoric acid-bonding starch having a Ca solubilization coefficient of not less than 10 as an index of a Ca dissolution activity of an oligosaccharide composition. |
