Abstract:

In this paper the effects of postharvest high CO₂(30%～80%) shock treatment on the storage quality and performance of Chinese Chestnut(Castanea mollissima Blume,cv. Dahongpao)at 0 ℃ were studied. The CO₂ treatment duration and CO₂ concentration were the main factors affect the quality. The ADH (alcohol dehydrogenase) activity and accumulation of alcohol was increased remarkably by the high CO₂ shock treatment. The longer the treatment time was and higher the CO₂ concentration was, the higher the ADH activity and alcohol concentration were. High CO₂ shock treatments affect the metabolism of starch and soluble sugar. 30%～50%CO₂could retard the decomposition of starch, while 60%～80% CO₂could increase the decomposition rate. The decay rate of chestnut treated with 40% CO₂ for 20 days was only 1% at the end of 120-day cold storage, and which was the best treatment to keep the storage quality and performance of chestnut among the high CO₂ shock treatments. The Chinese Chestnut was not hurt in all CO₂concentrations treatments if the treatment duration was not more than 10 days, but it become off flavor if the Chestnuts were treated for more than 20 days and the index of off flavor Chinese Chestnut was positive to the CO₂ concentration. The Chinese Chestnut could be reversibly hurt if CO₂ concentration was over high(>50) and time of treatment was over-long(>20 days) and the flavor was not recovered even at the end of storage.

Key words: Chinese Chestnut, High carbon dioxide shock treatment, Quality, Store resistance