Preparation and Characterization of Porous High‐Amylose Corn Starch

Abstract

AbstractPorous starch has been applied in numerous fields as a novel adsorbent because of its excellent adsorption capacity, safe properties, and abundant sources. In this study, high‐amylose corn starch, as a particular native starch, is used to prepare porous starch. α‐Amylase and glucoamylase are used for enzymolysis. The influence of five single factors on the adsorption capacity and loss ratio of porous high‐amylose corn starch are analyzed. Differences in enzymolysis reactions due to high amylose content are found. Response surface methodology (RSM) is used to optimize the preparation conditions and establish a prediction model for adsorption ratio. The optimum preparation conditions are determined: Activity = 1550 U g−1, pH value = 5.0, proportion of glucoamylase = 44%. At the optimum preparation conditions, the water absorption ratio reaches 123.60%, and the oil absorption ratio reaches 120.82%. The optimized samples are characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), differential scanning calorimetry (DSC), and apparent amylose content (AAC) and compared to existing porous corn starch. The results show that the optimized porous starch has better adsorption capacity, higher thermal stability, different crystal type, and complete particle structure than porous corn starch. These superior properties can be applied to many areas.