ABSTRACT

 Over the years African breadfruit has been an important natural resource for the poor, contributing significantly to their income and dietary intake. But despite the importance of the fruit, its production has been faced with several problems. To boost the processing of breadfruit, Kenneth Nwabueze, developed a breadfruit shelling machine, fabricated and constructed in the Agricultural and Bioresources Engineering department of Michael Okpara University of Agriculture Umudike. This dehulling machine which was constructed over 3 years ago, was reported to have a maximum dehulling efficiency of 86% at a speed of 225rpm, and a maximum dehulling capacity of l 76.2kg/hr at a speed of 425rpm,but upon evaluation through design analysis and calculations,it was observed that the machine was not designed according to required standards and specifications,and thus could not have achieved the above shelling effeciency and capacity. To this end, the required improvement and modification of the machine is to be carried out in the course of this project work. This includes: identification of the required improvements, modifying the design and operating principle of the machine, and testing the performance of the machine. To achieve this, careful analysis and calculations were carried out to detennine the critical and actual parameters needed. The appropriate construction materials were purchased from Timber market, Ikwuano, Abia State, while breadfruit was purchased from Ahiaeke market also in Ikwuano, Abia State. The purchased construction materials were used in the fabrication process, while the breadfruit was used for the testing of the machine. Finally, aside the obvious upgrade in the simplicity of the machine, the improved breadfruit dehulling machine was tested and the maximum dehulling efficiency found to be 81.2% at a calculated speed of 203 rpm, and maximum dehulling capacity of 37kg/hr. There were significant effect of moisture content on dehulling efficiency and dehulling capacity; reduction in moisture content of the breadfruit reduces the dehulling efficiency, but increases the dehulling capacity. Furthermore, a cleaning unit was designed to be incorporated in the machine to separate the breadfruit seeds from their hulls, but due to cost of extra materials and limited time frame, the prototype dehulling machine constructed was not incorporated with the cleaner. The Sustainability of the improved dehulling machine was achieved in terms of ease of maintenance and repair due to minimal moving parts and complexity.