Disclosed is a method for easily and efficiently separating a sialyllactose material from a dairy material by controlling the interaction between whey protein and sialyllactose by means of the processing pH.Specifically, sialyllactose can be concentrated and separated by performing simple operations including a step of concentrating a dairy material such as whey protein at a pH of 5.2 or less and a step of obtaining a low molecular weight fraction at a pH of 5.5 or more from a concentrated liquid that is obtained after the concentration step.In addition, since the separation of milk sugar and the mineral content can be carried out by the above-described operations, sialyllactose can be obtained at a high purity. Consequently, the thus-obtained sialyllactose material is highly valuable for food, pharmaceutical products and the like.
