Optimization of osmotic dehydration of tomatoes in a ternary system followed by air-drying

Osmotic dehydration and air drying technology represent a technique that can reduce post-harvest loss of fruits and vegetables. In this work the influence of osmotic solution composition (water/sugar/salt) and temperature on the osmotic dehydration of tomatoes (Lycopersicum esculentum) were examined. Tomatoes with and without skin were studied. The process of osmotic dehydration followed by air-drying was studied and modeled, so it could be optimized aiming the reduction of total processing time. The results showed the advantage of two different processes for the tomatoes with skin and without skin. Tomatoes without skin are processed faster using air-drying without submitting the fruit to osmotic dehydration. Whereas, the tomatoes with skin dry faster when submitted to an osmotic solution consisting of 35% of sucrose and 5% of salt at 60 °C prior to air-drying.