DETERMINATION OF SOME PHYSICAL AND ENGINEERING PROPERTIES OF COCOYAM
1.1 Background of the Study
The ever increasing importance of agricultural products together with the complexity of modern technology for their production, processing and storage need a better knowledge of the engineering properties of these products Cocoyam is regarded as the third most important root crop after yam and cassava in West Africa (Obomegheive et al., 1998). It is a staple food for millions of people living in the tropics. Onwueme and Simha (1991) reported that cocoyam cultivars have yield potentials for 37-75 tonnes /hectare and the corms and cormels are rich in minerals, vitamins and digestive starch grains It is however necessary to understand the physical laws guiding the response of these agricultural products so that machines, processes and handling operations can be designed for maximum efficiency and the highest quality of the final end products (Mohsenin, 1970).
For instance, the application of physical properties such as shape which is an important parameter for stress distribution in materials under load is important in developing sizing and grading machines and for analytical prediction of its drying behaviour (Esref and Halil, 2007). It is important to have an accurate estimate of shape, size, volume, density, surface area and other physical properties that may be considered as engineering parameters for that product, when biomaterials arc studied either in bulk or individually. Also, mechanical damage to seeds which occurs in harvesting, threshing, and handling can seriously affect viability and germination power, growth vigour, insect and fungi attack and also the quality of the final products (Mohsenin, 1970). Knowledge of mechanical properties (properties that have to do with the behaviour of agricultural products under applied forces) such as stress, strain, hardness and compressive strength is vital to engineers handling agricultural products. The determination of mechanical properties of agricultural products under static or dynamic loading is aimed at textural measurement of unprocessed and processed food materials the reduction of mechanical damage to agricultural produce during postharvest handling, processing, and storage and the determination of design parameters for harvesting and postharvest systems. Therefore, a rational approach to the design of agricultural machinery, equipment and facilities will involve the knowledge of the engineering properties of the products.
1.2 Objectives of the Study
The objective of this study is to determine the some physical engineering properties of cocoyam (shape, size, seed weight, volume, particle density, bulk density. porosity, surface area, angle of repose) which are considered important in the design of agricultural machinery, equipment and facilities for proper handling, conveying, separation, drying etc.
1.3 Significance of the Study
Due to the ever increasing importance of agricultural products together with the complexity of modern technology for their production, processing and storage, a better knowledge of the engineering properties of these products is necessary. However, it is essential to understand the physical laws guiding the response of these agricultural products so that machines, processes and handling operations can be designed for maximum efficiency and the highest quality of the final product.
1.4 Statement of the Problem
The shortage of processing and preservative machines and equipment for cocoyam, which may be due to the fact that data on the engineering properties of cocoyam required for the design of these machines are insufficient and not available in some cases. There is, therefore, a need for a comprehensive study of these properties to aid the design of processing and handling machines.
1.5 Scope of the Study
This work focused on the determination of some physical and engineering properties of cocoyam with a view to obtaining information required to ease the operations of processing and preservation.