Freshness retention in controlled-atmosphere-stored tropical fruits

许多热带水果的呼吸和蒸腾速率普遍高于其他水果，因此热带水果经常发生外部伤害和腐烂。本研究以番木瓜(Carica Papaya L.)、鳄梨(PerSea americana Mill.)、香蕉(Musa paradisiaca L.)、芒果(Mangfera Indica L.)为材料，研究了热带水果在气调和气调贮藏条件下的品质和耐贮性。结果表明，几种新鲜水果在中低O2(1%~3%)和高CO2(&lt；10%)的控制气氛下贮藏，可降低呼吸代谢，保持果肉硬度和色泽，从而延长这些水果的采后寿命。几种水果(番木瓜、牛油果)在氧气浓度低于1%的环境中，会出现成熟异常、内部褐变加剧的现象。本研究的目的是设计、建立和测试一种用于贮藏热带水果的功能性膜包装系统。与控制室中的正常空气成分相比，膜存储系统中实现了所需的较低的O2水平。文中还给出了膜面积选择的设计计算。结果表明，扩散膜贮藏技术适用于部分热带水果，控制乙烯、二氧化碳、水蒸气等污染物的增加是热带水果膜贮藏技术需要解决的问题。

The respiration and transpiration rates of many tropical fruits are generally higher than those of other fruits, therefore, the tropical fruits often occur external injury and incidence of decay. This study was aimed at establishing some useful retention method and assessing the quality and storability of tropical fruits in air and CA storage.Papaya (Carica papaya L.), avocado (Persea americana Mill.), banana (Musa paradisiaca L.), and mango (Mangifera indica L.) were evaluated for external appearance, flesh firmness, and internal quality.Storage of several fresh fruits in controlled atmospheres with moderately low O_2 (1% to 3%) and high CO_2 (<10%> levels at room temperature was shown to reduce respiratory metabolism, maintain flesh firmness and color, and thus prolong the postharvest life of these fruits. Several fruits (papaya, avocado) had abnormal ripening, and increased internal browning when exposed to an atmosphere containing less 1% O_2.Also, the purpose of this study was to design, build and test a functional membrane storage system for storing tropical fruits.Modified atmosphere packaging (MAP) used plastic membrane film for storing tropical fruits was evaluated. Required lower O_2 levels were achieved within the membrane storage system compared to normal air composition in a controlled chamber. Design calculations for selection of the membrane area are also presented. It can be concluded that the diffusion membrane storage aystem is applicable to some tropical fruits.The problems to be solved on the membrane storage technique for tropical fruits are to control the increase in ethylene, carbon dioxide, water vapor and so on.