Progress in identifying marker compounds to indicate sugar losses in sugarindustry processes

The most accurate determination of sugar losses in sugar processing would b e to analyse for a stable sugar degradation product, that is a marker compo und. In alkaline sugar processing streams, the occurrence of the alkaline d egradation of the invert sugars glucose and fructose is usually diagnosed b y a significant increase in colour. Unfortunately, many other reactions und er alkaline process conditions, can cause colour formation. This paper outl ines a more specific test to diagnose if the alkaline degradation of invert has occurred in process by detecting mannose, because under alkaline condi tions, mannose, glucose, fructose and, to a much lesser extent, psicose are in initial equilibrium via a reversible isomerization reaction. Detection of mannose in samples taken from industrial processes where alkaline condit ions dominate, confirmed that alkaline degradation of invert sugars had occ urred, and that mannose can be used as a marker compound for invert losses. A new and rapid ICIPAD (ion chromatography with pulsed amperometric detect ion) method has been developed to improve the detection of mannose in sugar industry samples. Oligosaccharides are formed in the breakdown of sucrose under acid and alka line conditions, and have strong potential as possible stable markers. Pote ntial oligosaccharide degradation product markers, formed across various su gar industry unit processes are reported and discussed, and compared to deg radation products in model study solutions. The model study sucrose degrada tion reactions were undertaken under simulated industrial conditions (65 de grees Brix; constant pH 5.45 - 9.25; N-2; 100 degrees C). Improved ion chromatography technologies for separation and fractionation o f sugar loss markers are described, as well as the nse of electrospray mass spectrometry to aid the identification of markers.