Abstract: In this paper, effects of high CO2 postharvest treatment on browning relative aspects of Chinese chestnuts (Castanea mollissima Blume.’Yanhong’) harvested from Huairou, Beijing were studied. 20 kg chestnut of each treatment was put into a big glass jar and treated with gas flow (40%～50% CO2, 3%～5% O2) for 3 and 5 days respectively at 20℃. Changes of browning relative aspects were analyzed at 0, 5, 10 days during shelf-life after treatment. It was showed that high CO2 treatment was a positive way to control browning of Chinese chestnuts. High CO2 treatment could decrease tannic content markedly after treatment, but it was not evidently in central layer cotyledon and interlayer cotyledon in later shelf life. Total phenol was lower than CK in cotyledon ectosexine, but it was higher than CK in central layer cotyledon and interlayer cotyledon when just finished the treatment. It was not evidently in the later shelf life. High CO2 treatment inhibited PPO activity and the activity markedly lower than CK during the whole shelf-life in three parts. It also reduced POD activity, but just in early shelf-life days. High CO2 treatment could reduce MDA content. The treatment of 3 days was preferably kept good integrality of membrane system. Considering all indexes synthetically, high CO2 treatment for 3 days better than 5 days.

Key words: Chinese chestnut, postharvest, high CO2 treatment, browning relative aspect