Characterisation of non-sugar compounds in molasses by LC- OCD-OND

MOLASSES IS WIDELY used in many fermentation processes producing significant quantities of highly coloured effluents. While, the majority of previous reasearch has focussed on the nutrient content and chemical composition of molasses, characterisation of the non-sugar compounds of molasses has not received significant attention in previous studies. In the present work, the dissolved organic material in six fermented molasses samples were characterised using Liquid Chromatography Organic Carbon Detection-Organic Nitrogen Detection (LC-OCD-OND). With this method dissolved organic matter for all molasses samples were fractionated and categorised into six groups; biopolymers, humic substances, building blocks, low molecular weight neutral, low molecular weight acids and hydrophobic organic carbon. Fermenting the samples reduced the signal from sugars. The LC-OCD-OND results suggest that in the sub 0.45?micron region the concentration of humic substances in cane molasses, is twice that of beet molasses fermented samples. While the relative average molecular weight of humic substance for cane molasses ferment is 2?3 times higher than that of beet molasses samples (514?662 g/mol). The analysis confirmed the presence of organic nitrogen compounds in the molasses samples as expected, though showed differences with nitrogen being assimilated from beet molasses, but only released by yeast grown on cane molasses. These findings may prove useful in the treatment of wastewater from molasses based industries and LC-OCD-OND is a useful for analysing molasses ferment composition, in conjunction with other measurements, as LC-OCD-OND was found to be limited in determining the organic acid composition of molasses.