| This paper searched the effects of ozone water cold shock and ozone treatments on winter-jujube,s quality, post-harvest physiological process, protective enzyme system and shelf life. On base of this, physiological and biochemical mechanism of ozone controlling the process of the ripeness and senescence of horticultural goods was deeply investigated to provide new potential approach and theoretical base for jujube,s storage in practice. Main results were as follows:1.Ozone water,s bactericidal capacity was closely related with its density, and it could kill animalcule effectively in a short time when reaching a certain density. As for sterilization of jujube, 2mg/L ozone could kill 99% animalcule in 60 seconds. Sterilizing effect in the refrigeration storage was also related with its density. 10mg/m3 ozone could kill more than 99% animalcule in 30min and 100% in 40min. This percentage increased obviously when the time prolonging in the first 30min.2.Both ozone water cold shock and ozone treatments kept winter-jujube,s firmness index, kept it from turnning red and fermentation softening, and maintained its appearance, especially its color. Meantime, these two treatments effectively prevented decrease of the content of titratable acid and Vc in winter-jujube, kept winter-jujube,s quality in storage period, and slowed down its progress of senescence. 2mg/L ozone water and 10mg/m3 ozone were the best treatments and caused no harm to winter-jujube.3.Ozone water cold shock evidently depressed the peak of the increasing total sugar, but could not postponed the coming of the peak. While ozone postponed the peak from about 40d to 60d.4.The fresh-keeping effect of cold shock increased with the increase in a certain extent of the ozone,s density. But strong oxidation of ozone with too high a density could destroy organizational structure of the pericarp resulting in pericarp wrinkling , the toughness of flesh strengthening and brittleness decreasing. High density ozone also oxidated the Vc in pericarp and caused a rapid drop of Vc content in early storage time.5.Ozone treatment effectively protected the cell membrane system, reduced the accumulation of MDA, obviously restrained the add of PPO activity and CAT activity , and slowed down its progress of senescence . Ozone water cold shock treatment decreased the peak of PPO activity and CAT activity, while ozone treatment postponed the coming of the peak and kept the activity in a high level. Besides, ozone also maintained the POD activity in a high level and weakened the membrane lipid peroxidation, as a result it gave winter-jujube better protection and slowed down its progress of senescence. A synthetical using of these two treatments was obviously prefered to using either of them singlely.6.The best approach to keep winter-jujube fresh by using ozone was precoolling for 24h under 0℃after harvest, and then treating by cold shock with 2mg/L ozone water under 0℃for 1min. After draining the water away by cold wind, the jujube was put under the temperature of -2℃to -3℃and relative humidity more than 95% in humidicool room. Ozone was given into humidicool room when the temperature difference between in and out reached to minimum everyday. The room was ventilated to let out ozone after closed for 30 to 40min. When the tested winter-jujubes stored in this condition for 100d, 95.62% remain good and the bad only account for 2.12 %.7.Precooling and cold shock treatment both prolonged winter-jujube,s shelf life and kept its commodity value, while ozone water cold shock had better effect on controlling softening. After a long cold storage, winter-jujube went rotten easily and had a short shelf life. Ozone treatment had a better effect in the storage but shortened its shelf life. The winter-jujube which was treated by 2mg/L ozone water cold shock at 0℃when coming out of the refrigeration storage prolonged its shelf life.
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