Abstract: Inulin is well recognized to be nutritious as food ingredient with good functionalities. Because of impurities including salts, crude protein, mono-and disaccharides, the crude inulin can not be widely used in human foods. Current purification operations have their own shortcomings, while a new operation of electrodialysis is evaluated with different operation voltage in the purification process of the crude inulin to remove salts and proteins. The tendency analysis of conductivity, pH, ash content, crude protein content, and sugar profile has indicated that electrodialysis is a feasible operation to remove the charged impurities, such as salts (70% removed after 1h) and crude protein (47% removed after 1h), without remarkable change of sugar profile. Being an economical and efficient purification operation, electrodialysis may alleviate the load of downstream operations.

Key words:  , inulin； electrodialysis； desalt； purification； oligosaccharide；