| Zanhuang Jujube, with thin peel and sweet crisp flesh, is affluent in nutrition. Its edible value and commercial value are very high. Zanhuang jujube can be used for the fresh food or process candied date and merchandise of dried fruits. With people to worth the nourishment valuer in fresh jujube, it's consumption increased gradually, and the marketforeground is vast. But after harvest, Zanhuang jujube is inclined to lose water and crimpled, with softening, rotting and Vitamin C lose, the nutrition and the high quality is not maintained under condition of room temperature.At present, the problem of fresh-keeping for Zanhuang jujube is not resolved, which affects the development of Zanhuang jujube greatly. In this paper, changes in quality and physiology of fresh Zanhuang jujube were studied under different storage temperature and different atmosphere conditions, and the optimum storage technology of the jujube was developed. The main research results were as follow:1 The study on the respiration of Zanhuang jujube in the different temperatures showed that the respiration peak were not found during storage after harvest. It was belong to non-cKmacteric fruit.2 The weight-loss rate of Zanhuang jujube during storage was reduced markedly by the low temperature combining with the appropriate lowoxygen content storage and package of PVC film bag with holes.3 with the storage time, the firmness of Zanhuang jujube reduced gradually, C A had a good effect on keeping firmness. The condition that temperature of 0℃ and the oxygen content of 2%~4% had the best effect on inhibiting softening, and excellent quality of the fruit was maintained after 80 days storage.4 During storage, Vc and titratable acid content decreased constantly, reducing sugar content increased gradually, total sugar content increased rapidly in the earlier stage and slowly in the later time, ethanol and MDA content rose slowly in the earlier stage and rose rapidly in the later time. The activity of PG enzyme and the activity of amylase decreased constantly.5 The activity of PG enzyme and the activity of amylase was negatively correlated withthe firmness of Zanhuang jujube significantly, r=-0.98l and r==-0;648 respectively.6 Zanhuang jujube fruit's freezing point is -3.5℃.7 The fruit peel was turned red in accordance with the Zanhuang jujube softening in proper orderly mutually. When the fruit was turned red, flesh of the fruits soften quickly. The changes of the fruit peel color could instruct the degree that flesh fruits softening.8 The study on store-resisting ability of Zanhuang jujube in different maturity stage showed that the whole-red Zanhuang jujube's store-resisting was low, so it was apt to market immediately or to store for short time after harvest. The white-ripening fruit and half-red fruit's store-resisting ability was high, but the white-ripening fruit was inclined to lose water; so it was not fit for storage, the half-red fruits was apt to store for a long time.9 The fresh fruits used to stored over a long period of time, must be picked by hand, and reserve the fruit' s handle, but do not take the leaf, even do not take the branches of the tree.10 Treatment the fruits with Propolis content of 1%. before storage, can reducing the loss of the fruits, prolong the fresh fruit period, improving its external appearance, increasing the merchandise value of the fruits.11 Compared with cold storage, controlled atmosphere storage(CA) had significant effects on keeping the fruit quality and delaying the fruit senescence, and the best CA storage technology was that: harvesting half-red Zanhuang jujube fruits, and reserving the fruit s handle → cooling at 0℃ on time→ rating and picking out the unqualified fruits →treatment with Propolis → packaging the fruit with PVC film bag → storage at 0℃, relative humidity of 90%- 95%, O2 content of 2%~ 4% and CO2 content less than 3%, After 80days storage, the percent of good fruit and edible fruit of Zanhuang jujube under this condition was 79... |
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