Sweetener - Corn and starch deashing

Color formation during sugar manufacture is affecting the quality of the final product. The most important color come from the melanoidin formation when monosaccharides (fructose and glucose) react with amino-acids as result of Maillard reactions. Other reactions occur, such as caramelization reactions which lead to the formation of browning products. Most of these molecules generating color have anionic characteristics.

Although the decolorization of liquid sugar almost always involves adsorption on some form of carbon, the use of ion exchange resins or synthetic adsorbent has partially replaced the traditional carbon by demonstrating better efficiency and cost effectiveness, with possible regeneration on-site.

Macroreticular Anion exchange resins are offering large pores and their strong base capacity are effective in chloride form. The chemistry or the degree of crosslinking of the selected SBA will depend on the raw material source and its origin. The regeneration will be performed thanks to a brine solution with small amount of caustic soda.

Decolorization of corn syrup and high fructose syrup will be performed on new generation of synthetic adsorbents, providing an optimized pore size distribution for the color adsorption and allowing a faster kinetic than traditional carbons. These adsorbents are also slightly functionalized to provide them a weak base character, increasing the efficiency for the color removal. These adsorbents are regenerable on site, and doesn’t need furnace regeneration, so finally is cost saving.

The temperature is normally between 70°C and 80°C to decrease the viscosity, so the resin has to be resistant to such operating conditions and the pH must be maintained neutral in processing sucrose solutions since basic pH will cause colored impurities.