Development and Performance Evaluation of a Modified Africa Bush Mango ( Irvingia gabomensis  ) Cracker

An African bush mango cracker was modified and fabricated to address the challenges of the conventional method of cracking nuts which involves striking the nut. The tedious nature of this process constitutes a major setback which restricts the production to a very small scale. The cracker consists of a frame, cracking table, slider–crank mechanism, hopper, feed chute, slot, cracking unit electric motor and reduction gear. The machine was evaluated with respect to throughput capacity and cracking efficiency at five moisture content levels (13, 15, 17, 20 and 25%) moisture content (MC) dry basis. At 13% MC; the output capacity was 7.13 kg/hr and cracking efficiency was 98% while at 15% MC; the output capacity and cracking efficiency reduced to 7.04 kg/hr and 96% respectively. Similarly, at 17% MC; output capacity and cracking efficiency further reduced to 7.02 kg/hr and 95% respectively while at 20% MC; the output capacity and cracking efficiency were reduced to 6.74 kg/hr and 93% respectively. There was a similar trend when the test was performed at 25% MC, as the output capacity and cracking efficiency showed a further reduction to 6.50 kg/hr and 90% respectively. These results were different from the old cracker that had throughput capacity and cracking efficiency of 4.32 kg/hr and 70% respectively. A significant trend was established which showed that as the moisture content of the nuts decreases, machine performance increases. Based on these results, drudgery and other hazards associated with manual cracking of the African bush mango are eliminated, the machine saves time and made processing of the seeds easier.