Physiological and quality responses of longan fruit to high O2 or high CO2 atmospheres in storage

Longan fruit (Dimocarpus longan Lour. cvs Chuliang and Shixia) were stored in controlled atmospheres (CA) of 4% O-2 plus 5 or 15% CO2, or 70% O-2 plus 0%. CO2 at 2 degreesC to determine the effects of different O-2 and CO2 atmospheres on physiology, duality and decay during storage. The results indicated that CA inhibited PPO activity, prevented peel browning and decreased fruit decay in comparison with modified atmosphere packaging (MAP with 15-19% O-2 plus 2-4% CO2). CA with the high O-2 concentration significantly decreased ethanol production in the flesh, maintained a lower pH value in the peel and maintained peel green color. Higher CO2 atmospheres (4% O-2 + 15% CO2) more effectively reduced decay and extended storage life of longan fruit by comparison with other CA treatments. Soluble solids contents were not significantly affected by different atmosphere treatments. Vitamin C contents, particularly in the fruit of cv Shixia, decreased rapidly after storage in all treatments. (C) 2002 Elsevier Science B.V. All rights reserved.