Development and performance evaluation of a garlic peeler.

Garlic peeling is a tedious, key, costly and time consuming unit operation in garlic processing. A power operated garlic peeler having a cylinder-concave mechanism was developed with an intention to reduce cost and time. Physical properties of garlic relevant for peeler development were identified and measured. The average length, width, thickness, geometric mean diameter, sphericity, weight of garlic segment and weight of 1,000 garlic segment were measured as 26.3 mm, 10.4 mm, 8.7 mm, 13.3 mm, 0.5, 1.8 g and 1,813 g, respectively. An experimental garlic peeler having cylinder covered with 10 mm thick rubber was fabricated and evaluated for its performance with crop-machine parameters viz., cylinder speed (29, 36 and 42 rpm), cylinder-concave clearance (8, 10 and 12 mm), moisture content (23.1, 27.7, 33.4 and 40.5 % wet basis) and concave mechanisms. Crop-machine parameters were optimized based peeling efficiency and they found to be cylinder speed of 36 rpm, cylinder-concave clearance of 10 mm, mild steel square (8 × 8 screen). Prototype garlic peeler was evaluated with the optimized crop-machine parameters. The peeling efficiency, yield of peeled garlic and unpeeled garlic, damage and peel separation were 86.6, 86.2, 4.7, 9.15 and 96 %, respectively with a machine throughput capacity of 27 kg/h and the energy requirement of 1.15 kw-h. Operation cost of the peeler was determined on the basis of fixed and variable cost and found to be INR 22.9/h. The developed garlic peeler saved INR 16.11/kg (94.99 %) and 1.63 (97 %) man hours in comparison to the hand peeling of garlic.