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伤和腐烂的事件。本研究旨在建立一种实用的保鲜方法，并评价热带水果在空气和CA贮藏中的品质和贮藏性。木瓜（Carica Papaya L.）、鳄梨（Persea americana Mill.）、香蕉（Musa paradisiaca L.）和芒果（Mangifera indica L.）的外观、果肉紧实度和内在质量进行了评价。结果表明，将几种新鲜水果置于低氧（1% ~ 3%）和高氧（<10%>）的可控环境中，可降低呼吸代谢，保持果肉硬度和颜色，从而延长果实采后寿命。几种水果（木瓜、牛油果）在o2含量低于1%的环境中成熟异常，内部褐变增加。此外，本研究的目的是设计、建立和测试一个功能性的薄膜储存系统，用于储存热带水果。对使用塑料薄膜薄膜包装热带水果进行了评价。与受控室中的正常空气组成相比，在膜存储系统内达到了所需的较低的O_2水平。并对膜面积的选择进行了设计计算。结果表明，扩散膜贮藏系统适用于某些热带水果。热带水果薄膜贮藏技术需要解决的问题是控制乙烯、二氧化碳、水蒸气等物质的增加。

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.