Effects Of Temperature And Modified Atmosphere Packaging (MAP) On The Postharvest Qualities Of Papaya

This study aimed to develop a system to extend the storage life of fresh papaya by selecting asuitable temperature and packaging method. The relevant enzymes were found out in the optimalstorage environment. The relationships between postharvest qualities and relevant enzymes wereas follows:(1) Compared the changes of firmness, total soluble solids (TSS), vitamin C, weightloss and color of papaya with storage period at8℃,13℃and25℃. The results indicatedpapaya got a reduction in firmness, TSS, vitamin C, weight loss and changes of color at13℃.(2) Compared the changes of firmness, TSS, vitamin C, weight loss and color ofpapaya with storage period in Atmosphere (AP), Non-modified atmosphere (Non-MAP),MAP (3%O2+8%CO2+89%N2). The results showed that the firmness, dissoluble solidscontent and Vc content most effectively can be maintained in MAP. It reduced the weightloss, maintained the skin color and qualities of postharvest papaya.(3) The activities of polygalacturonase (PG) and β-glucosidase were restrained, and thepeak time were delay in MAP. And in the same storage environment, the activities ofperoxidase (POD) increased, and the production of malondialdehyde (MDA) was alsocontrolled.(4) It found that there was Pearson correlation between the TSS, the sum of total sugar,and the same relationships were in the TSS, the summary total sugar, titratable acidity, andweight loss, the same to total sugar and titratable acidity. The Pearson correlation was alsoin total sugar and β-glucosidase, the value L*that described the lightness and the activityof POD, the activity of POD and the content of MDA. In addition, the firmness of papayacould be fit by the activities of PG, β-glucosidase and POD.