Method for preparing D-psicose crystal

A method of crystallizing D-psicose, the method comprising:

• concentrating a D-psicose solution to provide a concentrated D-psicose solution having a concentration of 80 Brix (%) to 85 Brix (%);
• performing rapid cooling of the concentrated D-psicose solution to 30° C. to 40° C. to provide a cooled D-psicose solution having a temperature between 30° C. and 40° C., wherein the rapid cooling is performed by heat exchange at a cooling rate of 5° C. to 20° C. per hour;
• placing, in a first crystallizer, the cooled D-psicose solution having a temperature between 30° C. and 40° C. and adding D-psicose crystal seeds to the first crystallizer;
• performing seeded crystallization of D-psicose in the first crystallizer while controlling a temperature of the D-psicose solution in the first crystallizer to stay between 30° C. and 40° C., which provides a D-psicose massecuite;
• placing the D-psicose massecuite to a second crystallizer and adding thereto a processed D-psicose solution to provide a crystallization mixture in the second crystallizer, wherein the processed D-psicose has a concentration between 80 Brix (%) and 85 Brix (%) and a temperature between 30° C. and 40°;
• and
• performing crystallization of D-psicose in the second crystallizer while controlling a temperature of the crystallization mixture in the crystallizer to stay between 30° C. and 40° C., which provides D-psicose crystals having a grain size of MA200 μm or larger.