The roles of soluble poly and insoluble tannin in the enzymatic browning during storage of dried persimmon.

The roles of total soluble polyphenols (TSP) and insoluble tannins (IST) in the enzymatic browning during the storage of dried persimmon slices packaged by different methods was studied. The color evolution was comprehensively evaluated within 18 weeks of storage, as well as determination the content variation of TSP, IST, and carotenoids. A series of simulated reactions were conducted to investigate the involvement of TSP and IST in PPO-catalyzed reaction. The results showed that N2-opaque packaging was a good way to alleviate this browning issue. The IST contributed preponderantly to the browning during the whole storage, while the contribution of TSP was little. And the degradation of carotenoids might be related to the color deterioration in the early storage. The IST participated in PPO-catalyzed reaction directly with the insoluble state. By contrast, only a small amount of TSP participated in PPO-catalyzed browning reaction, since it preferentially interacted with IST.