Design and Development of Pin Mill for Size Reduction of Turmeric (Curcuma longa) Rhizome

Abstract

In post-harvest operation of spices, grinding is important step. Turmeric rhizomes are generally long size and very hard to grind. In a small grinder, it is not possible to ground whole turmeric rhizome into powder. Cutting of turmeric then generally done manually. In some of the large grinder, the whole turmeric rhizomes fed into the grinder causes heat generation during grinding. The increased temperature during grinding results in loss of flavour and aroma. Cutting of turmeric was the pre-treatment given to the turmeric rhizome before grinding. Design of cylindrical drum, casing, hopper, screen, motor, pulley and supporting frame was done by considering different design consideration. The developed pin mill was having a capacity of 25-27 kg/hr. Pin mill cut whole turmeric rhizome into small pieces which had the average length, width and thickness of 9.10±0.51, 6.37±0.29 and 4.72±0.32 mm, respectively