Abstract
Excess intake of calories has been contributing to the increasingly poor health of the global population. The marked increase in obesity in adults and children has led governments around the world to introduce policies to reduce sugar intake by their population.
The purpose of this research was to generate a sugar replacer that will replace the bulking agent property of sucrose in food. This research aimed to isolate a novel oligosaccharide (xyloglucan) from hemicellulose-rich plant-cell-wall material as a sugar replacer. In this work, xyloglucan oligosaccharide was extracted from potato skin and whole chufa for use as a sugar replacer. The xyloglucan oligosaccharide (XGO) was physically characterised through dissolution tests, Thermal Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and X-ray diffraction (XRD). The XGOs were also chemically characterised through High-Performance Anion-Exchange Chromatography with Pulsed Amperometric Detection (HPAEC-PAD), Liquid chromatography-mass spectrometry (LC-MS), Nuclear Magnetic Resonance spectroscopy (NMR) and High-performance liquid chromatography/ Diode-Array Detection/ Mass spectrometry (HPLC/DAD/MS) using glucose as a control. The XGOs were also used to replace 25% of sucrose in a biscuit recipe and characterised against a 100% sucrose control in terms of colour, water activity, water content, and texture (hardness). This research found there were statistically significant differences in terms of colour for sucrose replaced biscuits with XGOs from potato skin and chufa when compared to the control. These biscuits were generally darker than the control, where potato skin XGO replaced biscuits yielded a deep brown colour and the chufa XGO replaced biscuits were golden brown. There were also statistically significant differences in terms of hardness between chufa XGOs replaced biscuits and the sucrose control.