Abstract: A method was established using high performance ion chromatography and pulsed amperometric detection for simultaneous analysis of 1-kestose (GF2), nystose (GF3), 1F-fructofuranosyl nystose (GF4), GF5, GF6, raffinose, stachyose and verbascose in infant formula milk powder. The chromatographic separation was achieved on a CarboPac PA20 column using a mobile phase composed of a mixture of sodium hydroxide and sodium acetate by gradient elution. Under the conditions optimized in this study, all the analytes were well separated, and the recoveries were 80.0%–103% with a relative standard deviation (RSD) less than 3% (n = 6). The method was rapid, accurate, reliable, and thus suitable for the determination of functional oligosaccharides in infant formula milk powder.

Key words: formula milk powder, functional oligosaccharides, high performance ion chromatography, pulsed amperometric detector