Abstract:

A high-performance anion exchange chromatographic (HPAEC) method for the analysis of fructooligosaccharide
(FOS) has been developed, using a CarboPac PA20 column and a PAD detector. This method clearly separated all the GFn
and FFn components, which can indicate the origin of FOS. Under the optimal conditions, the 1-kestose (GF2), neokestose
(neoGF2), nystose (GF3), 1-fructosylnystose (GF4) components of scFOS were analyzed in commercial FOS samples
with recoveries of 98.27%–99.72%, 97.32%–102.56%, 99.33%–101.81% and 97.38%–102.12%, respectively. The relative
standard deviation of the method was in the range of 0.55%–2.15%. The limits of detection (LOD) for GF2, neoGF2, GF3
and GF4 were 0.13, 0.19, 0.20 and 0.41 μg/g, respectively. In the concentration range of 0.3–18 mg/mL for GF2; 0.5–
20 mg/mL for neoGF2 and GF4; and 0.8–23 mg/mL for GF4, there was a good linear relationship between concentration and
chromatographic peak area, with correlation coefficients between 0.999 6 and 0.999 9.The new method has been successfully
applied to analyze added FOS in commercial functional foods, such as protein powder and milk powder.

Key words: fructooligosaccharides, high-performance anion exchange chromatography, qualitative and quantitative analysis