Nutritional Quality of Red Dates

Quality maintenance and ethanol metabolism of red date (Zizyphus jujube Mill.) fruits in response to modified atmosphere and controlled atmosphere (7% C[O.sub.2], 3% [O.sub.2] plus 90% [N.sub.2]) 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[degrees]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. Keywords: Controlled atmosphere, Ethanol, Modified atmosphere, Quality, Zizyphus jujube