Convective Drying of Turmeric Rhizome

Experimental trials on convective drying of turmeric (Curcuma longa L) rhizomes were conducted using factorial completely randomized design. Turmeric rhizome samples were cured for 30 min in 0.1 % solution of sodium carbonate and dried in a laboratory tray dryer at air temperatures of 50 °C, 60 °C and 70 °C with drying air velocity of 2 m.s-1. Drying air temperature was optimized on the basis of maximum retention of curcumin content, and b value of colour with minimum drying time and specific energy consumption. Optimization of drying parameters was carried out using numerical optimization technique. The optimum temperature for convective drying of turmeric rhizomes was found to be 60 °C with drying time of 29 hours

Convective Drying of Ginger Rhizomes and Slices

Experimental trials on convective drying of ginger rhizomes and slices (5 and 10 mm) were conducted using factorial completely randomized design. Ginger rhizomes and slices were dried at air temperatures of 50, 60 and 70°C with drying air velocity of 2 m.s-1 in laboratory tray dryer. Drying air temperature was optimized on the basis of maximum retention of oleoresin content, flavour strength and L* value of colour with minimum drying time and specific energy consumption. Optimum temperature for convective drying of ginger rhizomes and slices was found to be 60°C