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Packaging conditions of precut and prepared fresh vegetables were designed and tested experimentally in ability to keep freshness. As typical vegetables, water cress and onion were selected for this study. Respiration characteristics of the vegetables were measured by closed system method and the results were combined with gas permeabilities of available plastic films to design modified atmosphere packages of 200 g prepared vegetables at 5 C. The packages constructed as designed were then stored at 5 C and relative humidity of 90%. During the storage, package atmosphere, weight loss, microbial count, and organoleptic quality were monitored. The package constructed of 27 ㎛ thick LDPE showed 15 day shelf life for cut water cress, and tray packages stretch-wrapped with 13.7 ㎛ PVC and 10.9 ㎛ LLDPE gave shelf life of 15 days for cut onion. For stretch-wrapped packages, weight loss determined the shelf life, while microbial growth and off flavor development due to anaerobic respiration were shelf life determining factors for pouch packages of LDPE. Quality deterioration mode of precut and prepared vegetables depended on the produce and packaging conditions, and shelf life extension could be achieved by different type packaging for each produce.
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