SELECTIVE CRYSTALLIZATION OF MALTOSE BY ISOPROPANOL AND ACETONE FROM GLUCOSE–MALTOSE SYRUPS

Abstract

The solvability of glucose and maltose in water–based isopropanol and acetone has been studied. It has been revealed that with increase of organic solvent fraction the solvability of maltose in comparison with glucose sharply decreases. When the mass fraction of water in mixed solvent is less than 0.3, the difference in solvability of glucose and maltose in water–based acetone is significantly higher than their difference in water–based isopropanol. The obtained data served as the basis for the study of crystallization process of glucose and maltose mixtures of different compositions from water–organic solvents. It has been found that the highest efficiency of maltose crystallization from acetone and isopropanol is achieved during crystallization of the mixture containing 75 % of maltose and 25 % of glucose in case of twelve–fold exceedance by the volume of added organic solvent over the volume of water contained in initial syrup. The use of acetone gives a higher total efficiency of separation process, while the use of isopropanol gives a higher optimal content of dry substances (two times and more) in glucose–maltose syrup. Keyword: acetone, crystallization, maltose, glucose, isopropanol, syrup.