The influence of convection drying on the physicochemical properties of yacón ( Smallanthus sonchifolius )

Yacón root is a natural source of fructans, which has many potential benefits. Convective drying has been applied to increase the shelf life of yacón roots. However, this processing may lead to detrimental effects on the physicochemical functionality. The drying was investigated using different conditions (drying temperatures of 45 °C, 50 °C and 55 °C at a drying air velocity of 2 m/s and 60 °C at a drying air velocity of 2 m/s, 3 m/s and 4 m/s). The dried samples were compared to the original yacón with regard to their physicochemical properties. From all the properties that were studied, the color of the dried material and the elastic modulus of the reconstituted yacón were the most important properties being minimized respectively. The results of this investigation indicate that the best drying conditions, where the physicochemical properties of the samples are kept closest to the original material, are obtained either by using temperatures of 55 °C and 2 m/s or using higher temperatures but increasing the air velocity.