Osmotic dehydration of muskmelon (Cucumis melo):: Influence of blanching and syrup concentration

The influence of blanching and syrup concentration on the quality parameters of osmo-air-dried muskmelon product was investigated. Fruit samples were dehydrated with sucrose solutions at 40, 50 and 60 degrees Brix and the resulting products were analyzed for browning degree, ascorbic acid (AA) concentration and water activity. The values,for all three parameters decreased as the syrup concentration increased. Blanching treatment before the osmotic processing had no effect on browning but caused a decrease in AA concentration. Osmotically dehydrated fruits showed no browning increase for at least 4 weeks at 2C. A decrease of about 60% in AA concentration was observed within the first 2 weeks at 10C In contrast, AA loss was only observed after 2 weeks at 2C. The influence of storage time and temperature on AA retention was investigated by 2(2) factorial design. Statistical analysis of results showed that the two factors have a significant effect on AA retention. Osmotic dehydration may be an interesting alternative for processing of muskmelon as a pretreatment followed by cold storage or drying.