Physicochemical Properties and In Vitro Digestibility of Dual‐Modified Starch by Cross‐Linking and Annealing

Abstract

AbstractNative maize starch (NS) is modified by annealing (ANN) and cross‐linking (CL) processes, and also by using two different combinations of the ANN and CL processes (ANN‐CL and CL‐ANN). The effects of modifications on physicochemical properties and in vitro digestibility of starch are studied. The results show that CL‐ANN significantly (p < 0.05) improves swelling power and decreases solubility. The reduction in breakdown and setback indicate that ANN‐CL and CL‐ANN improve shear resistance and anti‐retrogradation effect of starch. All the modified starches exhibit native A‐type crystals but show higher crystallinity than native starch. The decreased enthalpy of the CL‐ANN starch is due to starch granule rupture during the treatment process. Scanning electron microscopy shows that ANN results in the formation of starch clusters, which are also present in CL‐ANN and ANN‐CL starches. The surface of CL starch is rough and partially cracked. CL‐ANN significantly (p < 0.05) increases the content of resistant starch to 10.74%. Physicochemical properties and digestibility of CL and ANN dual‐modified starches are related to the different combinations of the modification processes. Thus, dual modification using cross‐linking and annealing is an effective method to improve the properties of starch, thus broadening its application in the food industry.