The Study On Hypobaric Storage Mechanism And Technology In Dongzao Jujube Fruit

In this experiment five cultivars of Dong jujube fruits named Huanghua jujube, Zhanhual jujube, Zhanhua2 jujube (different cultivars), Shandong Wudi jujube, Dagang jujube, were harvested different mature stages for studying the respiratory type. Application of hypobaric storage was investigated to maintain the Dong jujube quality. We not only studied on the postharvest physiological and biochemical changes of Dong jujube;but also analyzed the mechanism of alcoholism, softness, TSS, Vc, PPO and the changes of storage quality during the hypobaric storage. At the same time, we studied different hot treatments on quality of Dong jujube fruit during shelf-life.Hypobaric storage significantly kept firmness and vitamin C content, reduced acetaldehyde and ethanol contents in pulp and respiratory intensity of Dongzao jujube, inhibited ascorbic acid oxidase and alcohol dehydrogenase activities, slowed down the rate of ethylene production in fruit. This five cultivars Dong jujube had significant climacteric peak, and this showed that Dong jujube had characteristic of climacteric pattern. Hypobaric storage significantly reduced number of climacteric peak, Huanghua jujube reduced 12.62%, Zhanhual jujube reduced 23.17%, Zhanhua2 jujube reduced 27.20%, Wudi jujube reduced 23.18%, and Dagang jujube reduced 21.40%. The effect of hypobaric storage had not postpone climacteric peak.This investigation also showed that the same jujube fruit in different ripening phases has different climacteric peak during hypobaric storage, and significantly higher at half-red stage than white stage, Huanghua jujube higher 12.62% at half-red stage than white stage, Zhanhua2 jujube higher 13.51% at half-red stage than white stage, Wudi jujube higher 17.05% at half-red stage than white stage, and Dagang jujube higher 46.95% at most-red stage than lesser half-red stage. This showed that they had different storage characteristic.The hot treatment showed that shelf-time of Dong jujube can be prolonged six minutes by 53 °C water.