Abstract: Lotus seed pod procyanidins (LSPCs) were extracted with 70% aqueous ethanol solution and purified by AB-8 macroporous resin adsorption, and their stability and thermal degradation kinetics were investigated. LSPCs were found to be very stable under low temperature, light-avoiding and weakly acidic conditions. NaCl, sucrose and glucose and the preservatives sodium benzoate and potassium sorbate had no obvious effect on LSPCs. H2O2 exhibited a great destructive effect on LSPCs, while NaHSO3 and VC had protective effect. LSPCs could be damaged by Fe3+, Fe2+, Pb2+ and Al3+, and other tested metal ions had a small effect. Four different sterilization methods were found to affect the stability of LSPCs to different extents, of which pasteurization had the least effect and high pressure steam sterilization had the largest effect. The thermal degradation of LSPCs complied with the first-order reaction kinetic process, and the activation energy Ea, and reaction constant k0 were 43.10 kJ/mol and 1.51×105, respectively. Moreover, a prediction model for the degradation of LSPCs was established. In validation experiments, the experimental results were observed to be in good consistency with the predicted ones, indicating that the prediction model is reasonable. 

Key words: lotus seed pod, procyanidins, stability, degradation kinetics