Effect of processing and simulated digestion on phenolics, antioxidant and hypoglycemic potential of winter jujube

The well- known winter jujube ( Zizyphus jujuba Mill. cv. Dongzao), has been proved to contain a series of bioactive compounds. To investigate the impact of processing and digestion on its phenolics, winter jujube was processed (steaming and freeze-drying) and digested. The treated winter jujubes' phenolic content, antioxidant capacity, and hypoglycemic potential were assessed. The results showed that processing reduced the number of total phenolics/flavonoids, antioxidant, and α-glucosidase inhibitory activity by 0.74–25.26%. With the exception of α-glucosidase inhibitory activity, which increased by 16.67–19.25% after digestion, these declines were more pronounced. After processing, the six discovered phenolics in winter jujube were mostly constant, but after digestion, their contents dropped by 6.72–38.64 %. These results suggested that following processing and digestion, the phenolic content and activity of winter jujube remained high (61.36–97.93%), indicating that freeze-drying and steaming are viable approaches to prepare and consume winter jujube.