Separation of glucose and fructose by freezing crystallization

Abstract This work comprises the implementation of a methodology for the study of an industrial crystallization process by freezing and cooling to be applied in the separation of sugars with industrial relevance (glucose and fructose). The main interest is the production of fructose. This sugar is obtained by sucrose hydrolysis in acidic solutions, which yields an equimolar mixture of glucose and fructose. The developed separation process is based on the solubility difference between the sugars. Experiments were carried out in a jacketed glass crystallizer where the solution coming from the sucrose acid inversion was submitted to a slow cooling. Since glucose has lower solubility than fructose, it crystallizes in the bulk as the temperature is lowered, thus it can be removed from the solution by fliltration or centrifugation. Best fructose‐glucose separation was achieved for a total sugar concentration of 50 wt%. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)