Changes in cell wall components of the orange flesh melon after post-harvest calcium treatment

The purpose of this work was to study the structural changes of the cell wa ll during the storage of 'Orange Flesh' melon submitted to postharvest trea tment with CaCl2. The content of cellulose, hemicellulase, pectic substance s and their degree of esterification, proteins and calcium was determined i n the cell wall of the flesh of the fruits stored under ambient temperature and refrigeration. The hot-water treatment for immersion in CaCl2 of 'Oran ge Flesh' melons stored under ambient temperature determinated apparently, an increase in the concentration of calcium bound to cell wall of the flesh of the fruits, besides partially inhibiting the breakdown of pectic substa nces and their de-esterification and to promoting the solubilization of pro teins of the cell wall, although it did not influence the changes of the ce ll wall compounds except that of the polyuronides, in the fruits stared und er refrigeration at 6 degrees C. In spite of calcium treatment, the storage of 'Orange Flesh' melon for 28 days at ambient temperature showed a decrea se in the levels of cellulose and protein and a substantial de-esterificati on of the pectins, although it did not affect apparently, the content of he micellulose and promoted a relative increase in the polyuronides and calciu m bound to cell wall. The fruits stored under refrigeration showed a few ch anges of the cell wall compounds, despite the fact that a reduction in the degree of esterification was noticed during the 31 days of storage.