Effects of different drying techniques on some nutritional components of tomato (lycopersicon esculentum)

Abstract

In this research, four drying techniques were applied for tomato (Lycopersicon escuientum) namely, hot air drying using tunnel type dryer, vacuum drying, freeze drying and sun drying and changes of food components of the vitamin C, lycopene, sodium (Na), and potassium (K) content were examined. As a result of drying applications, the initial moisture content of 94.73% of fresh tomato, dried tomato samples were found to range from 9.33% to 11.11%. Losses of nutritional contents of hot air dried samples increased with rising drying temperature. Loss of lycopene and Potassium content of vacuum dried samples at 75 °C were found lower compared to hot air dried samples at the same drying temperature. On the other hand increasing of drying time for vacuum drying increased loss of vitamin C. Vitamin C and lycopene content of sun dried samples were found higher compared to those of hot air dried and vacuum dried samples. Freeze drying method gave the best results in respect of all nutritional value criteria.