Effect of Some Oligosaccharides on Functional Properties of Wheat Starch

Purpose: To investigate the effects of oligosaccharides on the functional properties of wheat starch.
Methods: The blue value, retrogradation and pasting properties of wheat starch were determined. In addition, water activity (Aw), melting enthalpy and melting temperature of wheat starch paste were analyzed.
Results: Fructo-oligosaccharide (FOS) and xylo-oligosaccharide (XOS) inhibited the retrogradation of wheat starch. The peak viscosity of wheat starch with oligosaccharides increased from 3238 ± 8 to 3822 ± 10 cP, with the highest peak obtained for sucrose. The setback of wheat starch decreased (from 1158 ± 5 to 799 ± 6 cP), with the lowest setback for FOS. Aw of control sample changed significantly (falling from 0.978 ± 0.025 to 0.397 ± 0.013) when the drying time was from 6 to 12 hours, while the Aw of the samples to which different oligosaccharides were added only showed slight decrease (from 0.98 ± 0.019 to 0.854 ± 0.022). During storage, the Aw of all starch pastes decreased, and the Aw and melting enthalpy of the samples containing FOS and XOS were significantly lower than that of the control after 6 days storage at 4 and 30 °C.
Conclusion: A certain level of oligosaccharides can improve the functional properties of wheat starch paste and thus broaden its application prospects in food and pharmaceutical industries.

Keywords
Melting enthalpy; Oligosaccharides; Pasting properties,; Water activity,; Wheat starch