Development of maize starch with a slow digestion property using maltogenic α-amylase

In this study, maltogenic α-amylolysis was used to modulate the fine structure of starch responsible for the slow digestion property. The normal maize starch was treated using maltogenic α-amylase for 6 h and showed an increase of slowly digestible starch from 11.1% to 19.6%. Compared to the control starch, the iodine binding analysis showed that the wavelength of maximum absorption and the absorbance was substantially reduced with initial maltogenic α-amylase treatment. The maltogenic α-amylolysis decreased in molecular weight from 32.5 × 107 to 9.0 × 104 g/mol and increased in the number of shorter chains (DP < 13) from 25.5% to 44.8%, which was also accompanied by a reduction of longer chains (DP > 13). The increase in the amount of shorter chains was attributed to the slow digestion property of starch. These results suggest that the normal maize starches modified with partial maltogenic α-amylolysis produced new, fine structures with slow digestible characteristics.