舒波　魏永赞　石胜友　王一承　刘丽琴　李伟才

摘 要 以套罩及对照桂味荔枝为材料，统计贮藏期果实病果率，测定果实糖、酸、Vc含量，抗氧化酶SOD、POD及褐化相关酶PPO的活性，以此分析整株套罩对荔枝贮藏性的影响。结果显示：4 ℃条件下，套罩桂味贮藏两周无病果，且果肉可溶性糖在4.0～6.0 mg/g之间，可滴定酸在2.5～3.0 mg/g之间，品质较好。清除氧化自由基方面，贮藏两周后，套罩桂味果皮MDA含量显著低于对照，果皮Vc含量、POD活性与对照无显著性差异，但其SOD活性显著高于对照；酶促褐化方面，套罩桂味果皮PPO活性与对照亦无显著差异。与果皮不同，套罩桂味果肉MDA含量显著高于对照，但果肉Vc含量、SOD、POD以及PPO活性在二者间无显著差异。试验结果表明，果皮抗氧化能力是决定桂味荔枝耐贮性的主要因素，套罩桂味依赖较高的果皮SOD活性维持其清除自由基的能力，并以此增强果实贮藏性。

关键词 荔枝；糖、酸含量；抗氧化；酶活性

中图分类号 S667.1 文献标识码 A

Abstract Bagging whole litchi tree is a new health-harmless litchi production practice with provincial labor and low pesticide residues. However， the effects of bagging whole tree on post-harvest storage behavior of litchi fruit are still unknown. For this purpose， the diseased fruit rate， the content changes of sugar， acid， vitamin C（Vc）and malondialdehyde（MDA）were measured， and the activity variation of superoxide dismutase（SOD）， peroxidase（POD）and polyphenoloxidase（PPO）were determined during the storage of bagging whole tree and control‘Guiweilitchi fruit. The results showed that the‘Guiweilitchi fruit from the whole bagging tree was stored in 4 ℃ for two weeks with no rotten fruit， and the flesh sugar and acid contents were ranged from 4.0 to 6.0 mg/g and 2.5 to 3.0 mg/g， respectively. The peel MDA content in the whole bagging treatment was significantly lower than the no-bagging control after two weeks of storage. Referring to oxyradical scavengers， Vc content and POD activity in peel had no difference between the bagging whole treatment and the control， but the peel SOD activity in the bagging whole treatment was significantly higher than the control. Referring to enzymatic browning， the peel PPO activity had no difference between the bagging whole treatment and the the control. In flesh， the Vc content， SOD， POD and PPO activities were not different between the treatment and the control， but the MDA content was remarkably higher in the bagging whole treatment. The results suggested that compared with flesh， peel antioxidant was the main factor in determining‘Guiweilitchi storage， and the‘Guiweilitchi fruit of the bagging whole treatment relied on SOD to maintain its ability to scavenge free radicals which enhancing fruit storage.

Key words Litchi； Sugar and acid conten； Antioxidation； Enzyme activity

doi 10.3969/j.issn.1000-2561.2015.11.017

隨着生活水平的提高，人们对水果类食品的安全性越来越重视。利用新栽培技术生产的低农药残留果品愈发受到人们的欢迎。果实、果穗套袋技术已广泛应用于苹果、葡萄、梨、芒果、荔枝的栽培生产[1-4]，其能有效防治病虫害，降低农药残留量，提高果面光洁度，改善果实外观品质[5-7]。但是套袋需要较大人工成本且可能改变果皮性质与果实内在品质，进而对果实采后贮藏性产生影响[8]。相较于果实、果穗套袋技术，整株套罩为果树栽培新技术。虽然整株套罩技术还未在果树栽培上推广，但已有荔枝整株套罩研究。……