High‐Efficient Preparation of Cross‐Linked Cassava Starch by Microwave‐Ultrasound‐Assisted and its Physicochemical Properties

Abstract

Cross‐linked cassava starch (CCS) is prepared by a simple method assisted by microwave‐ultrasound using cassava starch as raw material. Several factors affecting cross‐linking reaction such as starch concentration, microwave–ultrasound power ratio, pH, reaction time, and amount of (NaPO3)6 are investigated by orthogonal experiment in terms of sedimentation volume for the CCS and the optimum conditions are established. Under these conditions, the sedimentation volume of the prepared CCS is 3.50. After cross‐linking, the crystallinity measured by X‐ray diffraction (XRD) decreases which is also confirmed by Fourier transform infrared (FTIR) spectroscopy. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) observations indicate that the obtained CCS is in rough spherical with the same average sizes as native starch. Thermogravimetric analysis (TGA) reports CCS exhibit higher thermal stability. In addition, the physicochemical properties of CCS are been studied. It is found that the freeze‐thaw stability, acid resistance, and thermal stability are highly improved, indicating that CCS has high application value in the food industry.