Insight into the retardation of retrogradation of chestnut starch by heat-moisture treatment with flavonoids

With the concern of rapid retrogradation of chestnut starch, the effect of heat-moisture treatment (HMT) with flavonoids on the retrogradation of chestnut starch was studied. The retrogradation of starch could be inhibited by HMT combined with flavonoid addition up to 65.88%. Flavonoids with different structures showed significant differences in retarding retrogradation, which followed the order of epicatechin>epicatechin gallate>oligmeric proanthocyanidins. Structural analysis, infrared spectra and theoretical calculations showed that hydrogen bond interactions between starch and flavonoids retarded starch retrogradation by inhibiting the aggregation of starch molecules to form crystalline and aggregation structures. The retarding effect of flavonoids was related to their steric hindrance, flexibility and phenolic hydroxyl number. Epicatechin with minor steric hindrance and more flexibility favored its hydrogen bond interactions with starch, leading to the best retardation effect of starch retrogradation. This study would provide a theoretical and experimental basis for creating high-quality chestnut products.