Process for producing a high-purity isomaltose

A process for the separation of isomaltose from a feed solution by the utilization of an ion exchange resin, comprising:

• (a) providing a feed solution containing at least 7% isomaltose based on the weight of the dry solid, the remainder consisting essentially of glucose and isomaltodextrins;
• (b) sequentially admitting predetermined volumes of the feed solution and water to a column of a strongly acidic cation exchange resin having sulphonyl groups of an alkali metal or alkaline earth metal form;
• (c) sequentially separating the effluents from the column into the following fractions:
• a first fraction rich in isomaltodextrins,
• a second fraction rich in isomaltodextrins, but highly contaminated with isomaltose,
• a third fraction rich in isomaltose,
• a fourth fraction rich in isomaltose, but highly contaminated with glucose, and
• a fifth fraction rich in glucose;
• (d) recovering the third fraction rich in isomaltose;
• (e) sequentially admitting into the column:
• the second fraction obtained in the step (c),
• a feed solution having an isomaltose content of at least 7% based on the weight dry solid, and the remainder consisting essentially of glucose and isomaltodextrins;
• the fourth fraction obtained in the step (c) and water;
• and
• (f) repeating steps (c), (d) and (e) in a cyclic manner.