Abstract:In this paper, the interaction between five polyphenols and corn starch was studied. The effects of polyphenols on the basic properties of corn starch particle size, iodine binding capacity and pH value were studied. The influence of properties such as the thermodynamics, microstructure and X-ray diffraction of polyphenols on corn starch in the process of retrogradation were analyzed. The results showed that the five polyphenols reduced the iodine binding capacity and pH value of the corn starch solution and increased the particle size of the corn starch. It can be seen from the thermodynamic properties that the five polyphenols reduce the thermal stability of starch and inhibit the retrogradation of corn starch. Among them, the addition of 5% tannic acid reduces the retrogradation ratio by 29.75%, which is the largest. Scanning electron microscopy (SEM) showed that a looser matrix could be caused in the dried polyphenol-starch mixture gel, while X- ray diffraction data show that the relative diffraction intensity of starch-polyphenol complex is lower than that of retrogradation starch. This indicates that polyphenol has a tendency to prevent starch retrogradation in the interaction with starch. 5 polyphenols may combine with starch through noncovalent interactions such as hydrogen bond or hydrophobic effect.