CHAPTER ONE
1.0 INTRODUCTION:
1.1 RESEARCH BACKGROUND:
After harvest, agro raw materials are normally handled, transported, dried, stored and further processed into food, feed and fiber.
In some basic post harvest activities, separation processes such as sorting, grading and cleaning are involved.
In mechanized operations, these post harvest processes are supposed to be carried out with machines and equipment. The engineering design and efficient operation of the post harvest processing machines and equipment require adequate knowledge of engineering properties of the bio-materials. Knowledge of engineering properties such as physical and mechanical properties constitute important and essential engineering data in the design of machines; storage structures; processes and controls as well as in the analysis and determination of the efficiency of machines, development of new consumer products of plants and animal origin and in the evaluation of the quality of food products. (Mohsenin,1986; Oluka, 1991; Oluka and Nwuba, 2001).
1.2 RESEARCH PROBLEM DEFINITION:
NERICA, also known as New Rice for Africa (NERICA) is a hybrid of the local African rice variety with high disease resistant traits and the high yielding variety of Asia. The rice is quite new to Africa and is currently being adopted and tried across the continent.
As a new product, there are on-going research studies on NERICA rice varieties. Studies on the engineering properties of the new rice variety are one of them.
Physical and Mechanical handling of the post harvest processing operation of NERICA require adequate knowledge of the physical and mechanical properties. This is the challenge of this study.
Knowledge of these properties will be valuable to Engineers, Food Scientists and Processors in designing of machines, storage structures, processes and controls as well as in the development of new products and quality assessment of food products.
1.3 RESEARCH OBJECTIVES:
The overall goal is to study the physical and mechanical properties of NERICA Paddy. The specific objectives include:
(i) To determine the physical properties of NERICA paddy such as shape, size, volume, density, specific gravity, sphericity and surface area.
(ii) To determine the mechanical properties of NERICA paddy such as rupture point, deformation, compressive strength, modulus of deformability, toughness, stiffness and the force at bio-yield point relevant to its milling and processing.
1.4 RESEARCH SIGNIFICANCE:
The information obtained are essential in the processing of rice paddy (NERICA) and prevention of mechanical damages during handling, processing and storage of the paddy. Equally, the knowledge of these properties will serve as a guide to designers of processing, storage and general handling equipments.
1.5 SCOPE OF THE RESEARCH:
The scope of this study is limited to physical and mechanical properties of NERICA relevant to its milling and design of machines for its handling and further processing operations. Only laboratory experimentation and measurements will be used as research procedures.