Optimizing aconitate removal during clarification

The inadequate removal of aconitic acid from sugar cane juice during the clarification process results in the acid contributing to processing difficulties, sucrose loss and extended down time. However, very few attempts have been made to remove the acid during normal factory operations. Batch clarification techniques were used in this study to investigate the effect of sucrose concentration, temperature, pH, time, defecant, and defecant concentration on aconitic acid removal from a synthetic juice solution. Methodology for determining the significance of each parameter to aconitic acid removal involved setting up a multiple factorial experiment looking at aconitic acid removal across all the parameters and their sublevels using the mixed linear modeling procedure in SAS (statistics analysis software) and applying results to raw juice. Results indicated that sucrose concentration, temperature and defecant concentration were the most significant parameters contributing to Aconitic acid removal, since aconitic acid removal was limited by cis-aconitic acid formation, the solubility of aconitates and competing compounds. Optimizing aconitic acid removal form synthetic juice points to reducing cis-aconitic acid formation by clarifying at low temperatures, reducing solubility of aconitates by increasing sucrose concentration and providing adequate reactants for competing compounds. Optimal conditions for aconitic acid removal from synthetic juice, when applied to raw juice resulted in a marginal increase in aconitic removal. However, prospects for increased aconitic acid removal from raw juice points to clarification of raw juice at the concentrated levels