摘要 |
A process for producing crystal 1-kestose wherein granular crystal 1-kestose in the form of large crystals can be produced at a high yield is disclosed. A high-purity solution of 1-kestose is concentrated to a Brix of 75 or higher; either seed crystals are added, or the solution is vacuum-concentrated to generate microcrystals for use as nuclei; then, a crystal growing step by vacuum-concentration and a microcrystal dissolving step for redissolving microcrystals which have formed in the concentrate are repeated at least twice each. Alternatively, a high-purity solution of 1-kestose is concentrated to a Brix of 80 or higher; either seed crystals are added, or the solution is allowed to initiate crystallization; after crystals are allowed to grow, a cooling step where the temperature is lowered by 5 to 20 DEG C from the previous step and a crystal growing step where the concentrate is maintained at the temperature to allow the crystals to grow are repeated at least twice each. Also, an enzyme for producing 1-kestose efficiently from sucrose is disclosed. |