Starch and ICUMSA color removal in sugarcane juice clarified by carbonatation

Resumo

The manufacture of sugar with sulfur dioxide during the clarification process faces market difficulties and rejection by consumers who are more and more concerned on food safety. The alternative may be sugar clarification with carbon dioxide which consists in adding carbon dioxide and calcium hydroxide to sugar juice at constant pH. Under these conditions, a calcium carbonate complex is formed which adsorbs and precipitates impurities. Current assay analyzes the clarification of sugarcane juice in a laboratory carbonatation process. Assays were performed randomly with a two-level factorial design with three replications at the center point to evaluate the effect of pH and carbon dioxide flow in clarification. Process efficiency was assessed according to rates of starch removal, ICUMSA color and calcium left in the juice. Rates of starch removal at 89.19 and 85.75% and of ICUMSA color at 92.93 and 91.66% were obtained, respectively, in assays with carbon dioxide flow at 200 NL h^-1 and pH at 8.0 and 9.0. Results show that total added calcium was almost removed as calcium carbonate.