Determination of Oligofructose, a Soluble Dietary Fiber, by High-Temperature Capillary Gas Chromatography

A high-temperature capillary gas chromatographic method was developed for the quantitative determination of oligofructose in foods and food products. Sample preparation involves oxymation and silylation of the extracted sugars. The oximetrimethylsilyl derivatives are analyzed on an apolar capillary column, with detection by flame ionization. The method is accurate, with recovery of spiked samples at >96%. Repeatability was excellent; RSD values of 1.1% were obtained. Other common oligosaccharides, such as malto-, isomalto-, and galactooligosaccharides, and levan do not interfere, making the method specific and reliable.