Preparation and Antioxidant Activity Evaluation of Tea Polyphenol Sweet Potato Starch Noodles

The effects of the amount and opportunity of tea polyphenols addition on breaking rate, iodine blue value, sensory quality and texture characteristics of sweet potato starch noodles were investigated and the effects of the retention rate and free radical scavenging rate of tea polyphenols under dry storage at room temperature and fresh a frozen were studied with noodles as the control. It was found that the quality of sweet potato starch noodles made by adding tea polyphenols before gelatinization was generally better than that made by adding tea polyphenols after gelatinization, and the optimal adding amount of tea polyphenols was 0.15 g/100 g. The results showed that the retention rate of tea polyphenols was 60.73% and the free radical scavenging rate decreased by 16.29% after 60 days of dry and normal temperature storage. Under the condition of wet and frozen storage, the retention rate of tea polyphenols in sweet potato noodle was 71.54%, and the free radical scavenging rate decreased by 10.38%. Moreover, the protective effect of sweet potato starch noodles on the content and activity of tea polyphenols under the two storage conditions was significantly better than that of flour noodles.