Nigerians and many of the West African countries grow yam and it forms one of the most prepared food in the region. Yam is consumed in various meal forms like: boiled yam, yam porridge, yam cake and pounded yam etc. People especially in urban area, prepare pounded yam occasionally mainly because of the drudgery involve in the process. This work is aimed at designing and constructing a yam pounding machine. It is to have a set of beaters mounted on a rotating shaft; such that the beaters hit the boiled yam until the desired soft paste is achieved. Other elements of the proposed machine are belt and pulley system, receptacle for holding the boiled yam and a prime mover. The machine is expected to pound 6kg of boiled yam in 7minutes with a minimum of 90% knot efficiency.
TABLE OF CONTENTS
Declaration - - - - - - - - - - i
Certification - - - - - - - - ii
Dedication - - - - - - - - - iii
Acknowledgement - - - - - - - - iv
Abstract - - - - - - - - - - v
Table of Contents - - - - - - - - vi
Abbreviation and Definations - - - - - - - x
1.0 Introduction - - - - - - - - - 1
1.2 Statement of the Problem - - - - - - 3
1.3 Aim - - - - - - - - - - 4
1.4 Objectives - - - - - - - - - 4
1.5 Significance of the Project - - - - - - 5
1.6 Scope of the Study - - - - - - - 5
2.0 Literature Review - - - - - - - - 6
2.1 Yam as a Staple Food - - - - - - - 6
2.2 Yam Production - - - - - - - - 9
2.3 Production of Pounded Yam - - - - - - 14
2.3.1 Traditional method of pounded yam production in asia and africa - 14
2.3.2 Production of pounded yam using powder yam - - - 16
3.5 Design Analysis and Selection of a Prime Mover - - - 37
3.6 Design Analysis and Selection of Chain and Sprocket - - 38
3.6.1 Table 6: Design calculation for chain and sprocket - - - 40
3.7 Design analysis and selection of the body - - - - 41
4.0 Manufacturing Process and Testing - - - - - 47
4.1 Manufacturing Process - - - - - - - 47
4.2 Tools Used for the Construction - - - - - 47
4.3 Construction Procedures - - - - - - - 49
4.4 Testing and Result - - - - - - - - 52
4.5 Discussion - - - - - - - - - 53
4.6 Maintenance - - - - - - - - - 53
4.7.1 Cost analysis - - - - - - - - 54
5.0 Summary, Conclusion and Recommendation - - - - 56
5.1 Summary - - - - - - - - - 56
5.2 Conclusion - - - - - - - - - 56
5.3 Recommendations - - - - - - - - 57
References - - - - - - - - - 58
ABBREVIATION AND DEFINATIONS
S.A.V-Mor Leather = Solvenka’ Akade’mia Vied Mor Leather
Yam is a root tuber which is grown in many African countries. People process yam for consumption in different ways. Most people boil yam for consumption with local butter or oil. It contains starch which gives energy to the body, yam can supply substantial amount of manganese and phosphorous. The tuber grows up to 2.5meter in length and weights about 10kg, it has a rough which is difficult to peal but which softens after heating (A. Odior, Orsah 2005).
Nigeria is by far the world largest producer of yam, accounting for over to 76 percent of the world production according to food and agricultural organization report. It has about 600 species in which five are economically important staple species, these are: Discorea rotundata (white yam), Discorea, alata (yellow yam), Discorea esculeit (Chinese yam), Discorea bulbifors (aerial yam) and Discorea clumentorum (trifoliate yam). Out of the species, discorea rotundata (white yam) Discorea alata (yellow yam) or water yam are the most common species in Nigeria.
It is consumed by both the middle and upper class and nearly all Nigerians consume it on a large scale during harvest season. It can be made in various forms for consumption such as, boiling it butter or oil or either preparing as porridge with some species.
But one of the commonest ways of preparing it is by pounding it into a sticky lump free mesh after boiling it and after that it can be eaten with soup. (Onyekwere 1987).
In African such as Nigeria, the pounding is mostly achieved traditionally with the help of a mortar and a pestle. The mortar is designed in a cuplike shape having a wide base to allow better sitting and griping on flour and the pestle a long wooden stick with a ball like head at the end or tips. Immediately the yam is harvested or brought, it is washed, pilled and then boiled, after boiling it is then poured inside the mortar and then pounded with the pestle (Oleniya; 1993).
In some West Africa country, yam is pounded by beating and stirring the already boiled yam with a wooden spoon until it is completely smooth. This process is laborious and takes time unnecessarily and needs one person to hold the boiled and and either to stir and beat the yam using the wooden spoon. (Oyekwere 1987).
Furthermore, in most part of Asia, pounding is done with stone and the yam is rolled with a wooden roller on a flat stone until a sticky mesh is obtained, this method is also laborious and unhygienic method of pounding (Onyekere 1987).
Also over the years the advert of Cadbury dried yam product popularly called poundo which did not required pounding with mortar and pestle gained more patronage, though fufu made from poundo was not as fresh as pounded yam and it used to be brownish in color. Though its process of preparation is much easier which only involve obtaining the poundo (i.e. yam flour) poured into a boiled water and stir properly. (Asedu 1992).
1.2 Statement of the Problem
Over the years, man have been faced with the problem of pounding operation and this has resulted into pounding using bear hands through the help of mortar and pestle. The process is laborious, time consuming and cannot meet demand where large quantity is required in places such as, hotels, restaurants and ceremonials events. As such, hotel and restaurants ends up not preparing pounded yam in large quantity. Field study conducted on some of the available yam pounding machine shows that they have large motor making the machine robust and is uneasy to handle, having fixed chambers, thereby making washing or cleaning of the machine difficult after use.
The aim of the project is to design and construct a machine for pounding 6kg of yam in a single operation at a maximum of seven minutes, having a reasonable size that can be handled easily with stainless steel chamber and beater.
To design and construct a yam pounding machine with a stainless steel pot as the pounding chamber
To select an optimum speed for beaters that will make pounding at 72kg/hr.
To maintain a small clearance between the rotary beater and the fixed receptacle in order to ensure minimum of 90% knot efficiency.
1.5 Significance of the Project
Nigeria is one of the world largest producers of yam. Nigerians, most especially people from the southern and middle belt of the country have high preference for pounded yam. Nevertheless many homes go for other dishes, the production of the pounded yam making machine will create more interest in consumption of yam when its produced in large quantity, the country stand the advantage of exporting excess product. Increase in production of the machine would bring about job opportunities for engineers, technicians and this will further provide a ground for the development of other food processing machines. As such, more job will be created, wealth and economy of the country will be boosted.
1.6 Scope of the Study
In other to pound yam, the following operational stages are involve. these includes; washing the yam tuber, peeling, slicing the yam into small pieces, boiling and pounding. The aim of this work is to design and construct a machine which only pound yam into a fine paste within a short period of time with less effort