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Weight-loss, general-appearance, yellowing, and compositions such as chlorophyll, carotenoid, vitamin C and nitrate, were studied to investigate the influence of pre-(cultivar and growing season) and post-(low-temperature and high-density polyethylene film packaging) harvest factors on the shelf-life and quality of leaf lettuce(Lactuca sativa L). Weight-loss was reduced by the treatment of high-density polyethylene film packaging, and more at 0∼1℃ than 4∼5℃. Leaf-lettuce grown in Winter lost less fresh weight than that grown in Autumn. In experiment on difference between cultivars, the reduction of weight-loss in $quot;Cheongchima$quot; lettuce was somewhat significant than that in $quot;Jeokchukmyeon$quot; lettuce. The tendency of changes in general appearance was similar to that of weight-loss. The yellowing of leaf lettuce during the storage was caused by chlorophyll degradation. Vitamin C content before the storage was 128.0 mg/100 g FW. in lettuce grown in Winter, 123.8 mg/100 g FW. in that grown in Autumn, and more $quot;Cheongchima$quot; lettuce than $quot;Jeokchukmyeon$quot; lettuce. In all treatment, vitamin C content decreased rapidly, and this tendency was more obvious at 4∼5℃ than 0∼1℃. The nitrate content of $quot;Jeokchukmyeon$quot; was 3812.6 ppm and that of $quot;Cheongchima$quot; was 2855.6 ppm before the storage. Nitrate content decreased more at 4∼5℃ than 0∼1℃ during the storage.
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