| Winter-jujube is a kind of well-known freshly consumed variety with charming red color. Its pulp is crisp, tender and juicy. It has been widely cultivated in the Bohai Bay areas and its production is increasing in recent years. Water loss, rotting and CO2 injury were main problems in long-term storage of winter-jujube. Humidicool storage with ozone treatment effectively deceased water-loss and rotting of Winter-jujube. The fruit was stored in a kind of box with hole and inputted fresh-air daily to avoid CO2 accumulation. Effects of stock, hormone, respiration, freezing temperature on the jujube nutrition and storage properties were studied. In addition, the impact of cold-shock treatment with ozonated water on the external microorganism, nourishment quality, pesticide content, the role of dipping CaCl2 solution treatment on softening and shelf-life of winter-jujube were studied. The main results were as follows:Stock tape and expansion hormone application are main factors influencing taste, nutrition and storage properties of winter-jujube. The yield of winter-jujube and average single fruit weight of the 'Suanzao' stock are less than that of 'Jinsixiaozao' stock, but its taste better in storage characteristic, so it is a kind of promising and popularizing variety. In the orchard management of pro-harvest, frequent usage of expansion hormone increased yield and single fruit weight, but due to growing too rapid, sugar content, vitamin C content and storage properties et al. reduced obviously. A hollow will be formed between fruit stalk and stone, and it can promote the fall rate of stalk, and form a nature wound, in which fungi can load largely, and cause rot of fruits.Respiration intensity was studied on winter-jujube of different maturity at room temperature and humidicool temperature respectively. The results showed that some factors can obviously affect the respiration intensity of winter-jujube, so in order to confirm respiration type of winter-jujube, there are many works to do.Several factors such as maturity degree and harvest time affected freezing point of winter-jujube. The test showed that the freezing point of winter-jujube is usually under -5℃, and it decreased during the storage. But placing the fruit at -3±0.5℃ in the humidicool room, chilling injury appeared in the seven days. So in the freezing temperature storage, the temperature of cold room should be kept in -1.5±0.5℃ at the beginning of the store, and dropped to -2.5±0.5℃ after 45 days.During the storage of winter-jujube, Pectinmethylesterases (PME) and amylase were the key enzymes in the process of softening of winter-jujube. Humidicool storage retarded increasing of PME, amylase activity, and improved D-Galacturonanases (PG) activity in one hand, in the other hand reduced Cx-cellulases activity, and delayed the decreasing of firmness and insoluble pectin content of winter-jujube.Humidicool storage inhibited lipoxygenase (LOX) and peroxidase (POD) activities of winter-jujube, and delayed decreasing of superoxide dismutase activity, increasing malondialdehyde(MDA) content, which are beneficial to keeping integrality of cell membrane.The cold-shock treatment with ozonated water (ozone concentration 2 mg/L, dipping 5 min in the 1 ± 1 ℃cold water) reduced quantities of bacteria and funguses of winter-jujube, and decreased the rate of loss weight, and extended shelf-life of the fruit. By the ultrastructures of winter-jujube pericarp, cold-shock treatment with ozonated water could clean out the waxiness of crackle and lenticel, which is helpful for exchange of fruit internal CO2 and air, and inhibit accumulating of ethanol concentration. In addition, cold-shock treatment with ozonated water decreased malathion, cypermethrin and deltamethrin content, and improved the safety quality of winter-jujube.Dipping fruits in 3%CaCl2 and 4 mg/L ozone for 5 min, at 18±1 ℃ decreased the activity of PME and amylase of winter-jujube, prolonged shelf-life of fruit, increased the rate and quality of commodities. In the proces...
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