| Chestnut is favorable for its nutritious and delicious qualities. It riches in necessary proteins, carbornhydrates, fats and other microelements. Chestnut has officinal and functional values for the human being. In recent years, the planting area and yield of chestnut increased year by year in our country. The water content and respiratory intensity of chestnut are very high, and the postharvest metabolism is also very quick. Chestnut is prone to go moldy, germinate and lose weight. It couldn't be stored for a long time. The main foreign country that studying on the storage of chestnut is Japan, but mainly focused on cold storage. In our country, the researchers began to study on the keeping-fresh and storage techniques from 1970s, and obtained some accomplishments, such as sand storage, CA storage and low-temperature storage, but didn't get the problems of going moldy and losing weight resolved.Ozone treatment, decompression treatment and ozone-decompression treatment were adapted during the storage of chestnut. The influences on the postharvest physiological change and storage effects were focused on, and the most suitable technical parameters for the storage of chestnut were obtained.1. Chestnut was supposed to belong to the kind of fruit without climacteric. Ozone treatment could slow down the respiration intensity of chestnut obviously. There was a positive correlation between the concentration of ozone and inhibitory effect within the ozone concentration of 150μg/L, and negative correlation between the concentration of ozone and inhibitory effect when the ozone concentration was higher than 250μg/L.2. The activity of amylase increased during the storage of chestnut. Ozone treatment could restrain the activity of amylase. And this restrained the degradation of chestnut starch, and slowed down the change of total sugar and reducing sugar. The better concentration of ozone in the treatment is 150μg/L, lower than or higher than 150μg/L would reduce the restraining effects.3. Lower ozone concentration could make the change of CAT activity more slowly reduce the relative conductivity of chestnut during the storage, and 150μg/L was a suitable concentration. The CAT activity and the relative conductivity would bereduced when the concentration was higher than 25QMg/L, the POD activity would be reduced and the relative conductivity would be increased when it was higher than 15Qug/L.4. Ozone treatment could reduce the weight loss rate of chestnut obviously;the best concentration of ozone was 15Qug/L. And also ozone treatment was a very good method that reduced the decaying rate of chestnut evidently. Chestnut was treated with 150/ig/L ozone for 0.5 hour every 10 days. Stored for 180 days, 93% of chestnut was still fresh. Lower than 150/^g/L, the keeping-fresh effect was not very good;and higher than 150//g/L, the ozone would make bad hurts to the tissues of chestnut.5. Decompression treatment could inhibit the respiration intensity of chestnut evidently. There was a negative correlation between the pressure and the inhibitory effect on respiration intensity when the lowest pressure was higher than 40.5kPa.6. Activity of amylase was inhibited by decompression treatment, and then the degradation of starch was avoided, and the changes of total sugar and reducing sugar were slowed down. There was a negative correlation between the pressure and the inhibitory effect on amylase activity, degradation of starch, and the changes of total sugar and reducing sugar when the lowest pressure was higher than 40.5kPa.7. The activities of CAT and POD could be inhibited with decompression treatment. There was a negative correlation between the pressure and the inhibitory effect when the lowest pressure was higher than 40.5kPa. Decompression treatment had the same effect on the relative conductivity, and there was also a negative correlation between the pressure and the reducing effect when the lowest pressure was higher than 40.5kPa.8. Decompression treatment could inhibit the weight loss rate of chestnut obviously;and there was a negative correlation between the pressure and the inhibitory effect when the lowest pressure was higher than 40.5kPa. Stored for 180 days at the pressure of 40.5kPa, 90% of total chestnut would be kept fresh.9. Ozone-decompression treatment would inhibit the physiological changes in chestnut well, and keep the sensory quality of chestnut well. The best quality of chestnut could be obtained at the storage condition of 200//g/L ozone and 40.5kPa.10. The results of chestnut storage experiments indicated that the best storage conditions with ozone-decompression treatment were: enough moisture in the storage environment;storage temperature -l±0.5°C;treated the chestnut with 200iwg/L ozonefor 0.5 hour every 10 days, and then got rid of ozone, kept the pressure at 40.5kPa. At these conditions, 95% of total chestnuts would be kept well for 180 days.
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