Disclosed is a method of obtaining a sialyllactose material from a milk material, the method comprising: a)removing proteins from the milk material to obtain a protein-free liquid b)adjusting the pH of the protein-free liquid to obtain a pH-adjusted liquid and c)concentrating the pH-adjusted liquid by an ultrafiltration (UF) membrane, wherein when skim milk is the milk material the pH of the protein-free liquid is adjusted to 5.6 to 6.6, and when whey is the milk material the pH of the protein-free liquid is adjusted to 3.6 to 5.5.
