Corn porous starch: preparation, characterization and adsorption property.

This study was carried out to develop a new type of modified starch based on α-amylase and glucoamylase. The structural and chemical characteristics of the porous starch were determined by Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The potential application of the porous starch as an adsorbent was evaluated using methyl violet as an adsorbed model. The adsorption capacity was optimized by investigating the reaction factors, including the mass ratio of α-amylase to glucoamylase (m(α-amylase)/m(glucoamylase)), the mass ratio of total amount of enzymes to starch (m(enzyme)/m(St)), the ratio of liquid volume to starch mass (V(H2O)/M(St)), pH value of the reaction solution, enzymatic reaction temperature, and enzymatic reaction time. The hydrolysis ratio of each sample was also determined to investigate the effect of different reaction conditions on the hydrolysis degree. The results suggest that the porous starch has a more excellent adsorption capacity than the native starch, and may be expected to have wide potential applications in many fields.