oA method for manufacturing a modified whey composition said method comprising a solution preparing step for preparing a starting whey solution with the use of a whey composition containing whey protein and a heating step for heating the starting whey solution wherein: the solution preparing step involves a treatment of adding an alkali to the whey composition; the pH value of the starting whey solution is 6.8-8.0 and the protein concentration in the solution is 1.3 mass% or less; the starting whey solution to be heated has a calcium content of 400-700 mg/100 g of solids; and the heating treatment is conducted at 80-150 °C for 1 sec to 30 min.