CHARACTERISATION OF DISSOLVED ORGANIC MATTERS IN MOLASSES BY USING LC-OCD-OND

MOLASSES IS WIDELY used in many fermentation processes. As wastewater from molasses fermentation can pose an environmental problem, scientific characterisation of the non-sugar components of molasses is worthwhile. While most previous work has focused on the nutrient content and chemical composition of molasses, the present study investigates molasses fractionation based on molecular weight distribution. In this study, size exclusion liquid chromatography organic carbon detection (LC-OCD) was utilised to characterise the dissolved organics in six molasses samples. Through this method, the dissolved organic matter of each sample was fractionated into six groups, which could then be quantified. LC-OCD results suggest that, in sub 0.45-micron region, the major fraction (~80%) of each diluted molasses sample consisted of low molecular weight (LMW) compounds (<350 Da), which was expected to be due to the sugar content. The analysis also showed a small amount of organic nitrogen compounds in the molasses samples, which was expected as melanoidin, thought to be a sugar amino acid polymer. No Hydrophobic Organic Carbon (HOC) was found in beet molasses samples, while this component comprised up to 11.5% of organics in cane molasses. Our findings revealed that, while there are similarities between the brix level of molasses samples, there are differences in terms of viscosity, total suspended solids and nitrogen content of different types of molasses. Therefore, these findings may have useful practical implications in the broad range of molasses-based industries, and LC-OCD may be a useful technique for analysing molasses composition.