Study on the effect of tea polyphenols on thermal and pasting properties of two kinds of starch

The effect of tea polyphenols (TP) on thermal and pasting properties of waxy maize starch and octenyl succinic anhydride starch (OSA starch) was investigated.The gelatinization and retrogradation properties were tested using a Differential Scanning Calorimeter.The pasting properties were assessed by a Rapid ViscoAnalyzer.It showed that the gelatinization temperature and gelatinization enthalpy of these two kinds of starch obviously decreased (p<0.05) with the increasing level of TP.After 7 days storaged at 4℃, the retrogradation enthalpy and recrystallization of these two starches decreased (p<0.05) with the increase of TP content.Waxy maize starch with 15% TP and OSA starch with 10% and 15% TP didn’t appear recrystallization and retrogradation enthalpy after storage of 7 days.The viscosity of OSA starch decreased with the increase of TP, especially when adding 15% TP, the peak viscosity, trough viscosity and final viscosity decreased most while waxy maize starch didn’t show a certain regularity.Coclusion:The overall results demonstrated that TP could reduce the gelatinization temperature and enthalpy, inhibit retrogradation of these two kinds of starch and could reduce paste viscosity of starch to some extent.