Application of convective- microwave and convective drying of ashwagandha roots was investigated. Ashwagandha roots of uniform size were used in the drying experiment which were conducted air temperatures of 40°, 50° and 60°C, air velocities of 1.0 and 1.5 m/s and microwave power level of 2,4 and 6W/g. A laboratory convective dryer which was already developed had the provision of regulating of air temperature and air velocity and were conducted air temperatures 40°C, 50°C and 60°C, air velocities of 1.0 m/s and 1.5 m/s. Convective -microwave drying and Convective drying was carried out till the moisture content of the ashwagandha roots reduced from initial moisture content of 5.06 kg water/kg of dry matter to an ideal level of 0.06 kg water/kg of dry matter. The effect of air velocity increment in convective drying reduced the drying time thereby increasing the drying rate. The quality attributes of fresh and dehydrated ashwagandha roots were evaluated for colour parameter (L, a, b values), total alkaloids content. The rehydration ratio was also determined for dehydrated roots. The quality attributes of the samples were compared convective -microwave drying, convective drying technique with sun drying. The result revealed that the power level of 6W/g, velocity of 1.5 m/s and air temperature of 50°C gave a good quality dehydrated ashwagandha roots in convective-microwave drying process and convective drying with air velocity of 1.5 m/s and air temperature of 60°C gave a good quality dehydrated ashwagandha roots in convective drying process as compared to sun drying.

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