Design and Development of Cumin Destalker Machine

Cumin (Cuminum cyminum L.), a seed spice of family umbelliferae, is valued as aromatic, preservative, flavoring, and therapeutic agent in the food and pharmaceutical industry. The quality standards of cumin are closely associated with processing techniques. A tiny stalk attached to cumin is one of the major quality concerns in threshed and cleaned product. To remove this stalk, a centrifugal type mechanical cumin destalking unit was developed and evaluated. Developed unit consists of a frame, vibratory feeding assembly and discharge chute, horizontal plate type destalking assembly, and a drive unit. Feed rate (30, 50, and 70 kg/h), clearance between the plates (5, 8, and 11 mm), and speed of plate (550, 750, and 950 rpm) were taken as study variables and the performance of the destalker was evaluated in terms of destalking efficiency and broken percentage (damage). Performance was evaluated under single-pass and multi-pass conditions and also with and without pre-drying. Best performance was observed when cumin was destalked under multi-pass mode with pre-drying at a feed rate of 50 kg/h and plate speed of 750 rpm. At optimum operation conditions, the machine was found to have a destalking efficiency of 82.03% with 10.88% damage.