Process of purification of sialyllactose comprises obtaining sialyllactose enriched raffinate by ion exclusion chromatography of a solution containing the sialyllactose on a strong cationic resin in monovalent majority, i.e. sodium or potassium form. An independent claim is included for a process of enriching maternized milk with sialalylactose comprising production of the sialyllactose by the process and addition of the obtained sialyllactose with maternized milk or its precursor.
