Nutritional Quality of Red Dates (Zizyphus Jujube Mill.) in Response to Modified and Controlled Atmospheric Storage Conditions

Quality maintenance and ethanol metabolism of red date (Zizyphus jujube Mill.) fruits in response to modified atmosphere and controlled atmosphere (7% CO2, 3% O2 plus 90% N2) were investigated in the present study. Results showed that modified atmosphere and controlled atmosphere significantly maintained higher titratable and ascorbic acid contents during storage at 0°C for 32 days. In addition, ethanol accumulation and alcohol dehydrogenase activity indicated that ethanol metabolism in red dates was substantially inhibited by modified and controlled atmospheric storage conditions. Furthermore, the browning and polyphenoloxidase activity was also delayed by both atmospheric conditions compared with control. By evidence of sensory evaluation, results confirmed that both modified and controlled atmosphere packages contributed to the maintenance of better sweetness, sourness, firmness, juiciness and date flavor as well as overall preference after cold storage. Nonetheless, no significant difference on decay index of red dates was observed between changed atmospheres and untreated control after storage. Results from the present study are of importance to the red date industry on theoretical and practical aspects.

Chemical Characterization and Anti-inflammatory Activity of Polysaccharides from Zizyphus jujube cv. Muzao

Polysaccharides fromZizyphus jujube cv. Muzao(ZMP) were extracted by ultrasonic-assisted extraction with acidic buffer. The chemical composition and antioxidant and anti-inflammatory activities of ZMP were evaluated. The results revealed that ZMP had a molecular weight of 89.90 kDa and consisted of arabinose, galactose, glucose, rhamnose, and mannose, with molar percentages of 4.52 %, 2.64 %, 1.04 %, 0.49 %, and 0.41 %, respectively. Based on Fourier-transform infrared spectroscopy, ZMP belonged to the type I rhamnogalacturonans family. In vitro antioxidants assays revealed that ZMP had remarkable antioxidant activity in a dose-dependent manner. Proinflammatory cytokines, such as interleukin-6 and tumor necrosis factor alpha, were suppressed by ZMP in lipopolysaccharide-treated RAW264.7 cells. Overall, the results revealed that ZMP has potential applications as a natural anti-inflammatory agent.