Effect of Osmotic Dehydration Pretreatment on Melon (Cucumis Melo) Drying Time

Drying has been the most widely used method of dehydration since ancient times; however, its use generates high energy costs, due to the long duration of the process. On the other hand, the exposure of foods to high temperatures for long periods of time tends to considerably affect not only their organoleptic characteristics, but also their nutritional content. An alternative to these problems is osmotic dehydration, which allows generating a partial dehydration without deteriorating the food's properties. In this way, the food begins its drying process with a reduced moisture content, thus reducing the drying time, saving energy costs and avoiding exposing the food to heat for long periods of time. The methodology consisted of evaluating the osmotic dehydration process of melon at osmotic concentrations of 45 °Bx and 60 °Bx and immersion times of 120 and 180 minutes, to be subsequently dried at 50°C until reaching a minimum humidity of 15%. The osmotic dehydration tests demonstrated the significance (p < 0.05) of the factors studied in water loss, weight loss and solids gain. Water losses between 48.393% and 68.204% were achieved, where drying time was reduced in a range between 23% and 46%. The treatment that generated the shortest drying time was the one that had as pretreatment conditions of 60°Bx and 180 minutes of immersion.