Title : Drying characteristics, functional, and physicochemical properties of Raphanus sativus L. (Figl) leaf and petiole: In case of convective drying condition
Abstract:
Figl is one of the underutilized crops in most parts of Ethiopia and is rarely used as a source of income and food in the southwest part of the country. Investigating the effect of drying temperature on the quality of the leaf and petiole part of Figl is very important to use the leaf and petiole for food formulation or use as a food ingredient in developing countries to overcome the problem of food security. This study investigated the effect of drying temperature (sun, 40 ºC, 50 ºC, and 60 ºC) on drying rate, effective moisture diffusivity, color, and functional and chemical properties of leaf and petiole. The effective diffusivity values changed from 4*10-12 to 8.2*10-12 m2 /s and 2.1*10-08 to 4.9*10-8 m2 /s for leaf and petiole of Figl, respectively, within the given temperature range. The bulk density of the leaf and petiole of Figl were in a range of 0.20-0.35g/mL and 0.27- 0.41 g/mL, respectively. The result indicated that drying rate, moisture diffusivity, water activity, ascorbic acids, and delta were decreased with drying temperature. In contrast, the functional properties of both leaf and petiole parts were increased with drying temperature. Comparatively, the petiole part of Figl showed better results in terms of functional and chemical properties than the leaf at all drying temperatures. From the study results, in terms of functional and chemical properties, drying petiole at 50 ºC for 120 minutes hour was found to be the optimum temperature for better quality.
