THE PRODUCTION OF YAM FLOUR

ABSTRACT

The project dealt on the production of yam flour from yam chips. The yams were peeled and washed, 100grams samples coded sample A to G were subjected to two different drying conditions. Some were dried using the sun drying method while the others were dried through oven drying method kept at constant temperature of 500C, sodium bicarbonate was added to some of the samples, all these were done to obtain a flour with the best colour and texture quality. From the results obtained, it was observed that sample B yam boiled with sodium bicarbonate and dried with oven gave the best result and quality when tested with hot water, this was as a result of the drying condition used, the constant temperature maintained and the presence of the sodium bicarbonate used which helped in achieving the result. Generally, the samples dried through the oven drying method at 500C gave better colour and result of the yam flour when tested with hot water more than other samples dried by sun drying and this was due to the stability in temperature in the oven drying method used.

CHAPTER ONE

1.0 INTRODUCTION

1.1 Background Of The Study

Yam dioscorea spp. is a multispecies crop that originated principally from Africa and Asia before spreading to other parts of the world Hahn et al.,1987. It belongs to the family of dioscoreae within the genus dioscorea and serves as a staple crop in west Africa.Asiedu et al., 1992. There are many cultivars of yam, though only six are important as staple foods in the tropics. the economically important species grown are Dioscorea rotundatawhite yam,D.alata yellow yam,D.bulbifera aerial yam, D.esculenta Chinese yam and D.dumenterum trifoliate yam. Yam tubers which is the most important part of the plants can be stored longer than other root and tuber crops. This ensures food security even in times of general scarcity. Yam is the third most important tropical root and tuber crop after cassava and sweet potato fu et al., 2005. West Africa is the leading producer of yam and grows over 90 of the worldwide production 40 tonnes fresh tuber/year followed by the west Indians where Jamaica is the leading producer FAOSTAT,2004. Nigeria is the worlds largest producer of yams followed by Ghana, ivorycoast and togo FAO,2003. Both fresh tubers and yam flour are now exported from Ghana and Nigeria to developed countries such as united kingdom and united states of America. These are mostly patronized by emigrants from growing regions according to the Nigerian export promotion council NEPC Nigeria realized N56 billion in 2007. Sustainable production and utilization of yam are important steps in enhancing food security and alleviatind poverty particularly in west Africa where it is estimated to provide more than 200 dietary calories each day for over 60 million people Nweke et al.,1991., FAO 2002.

1.2 STATEMENT OF THE PROBLEMS

The principal problem in yam production that has been identified is the high cost of seed yam, high labour requirement, diseases, pest as well as high post harvest lossesOrkwor 1998.another constraint to yam production is the limited processing technology. About 30 of harvested yam tubers are lost to waste. The bulkiness of fresh transport and low margins for both farmers and traders are thus a matter of serious concern in the urban market Cooke et al.,1988.

During the processing of yam through sundrying method,the problem encountered is the loss due to potential contamination of the product variability in drying time, rain damage and so on. Ohweever, D.alata fresh texture is usually not firm as the D.rotundata white yam and less suitable than other species for the preparation of the most popular food product from yam in the west Africa regionWirekomanu et al.,2011.

1.3 OBJECTIVE OF THE STUDY

1.3.0 MOTIVATION

The growing need for the variety of food in Nigeria has become a primary concern for the urban and rural households in Nigeria. In recent times, the concern has raised much researchers interest to do related studies. As reported in many different studies around the world, food security is a common problem.

1.3.1 OBJECTIVES

The present study aims at carryout an experiment on fresh yams, optimize the drying parameters and investigate the effect of drying conditions on the quality of the yam. To result to this, the present study which will address particular issues food drying could stimulate producers, farmers, agriculturists, educational practitioners on the phenomenon of drying to enhance the quality of yams to solve past harvest losses.

1.4 SCOPE OE THE WORK

To carryout drying experiment on fresh yams and optimize the drying parameters.

To determine the effect of drying on the quality properties

Process the yam samples into chips and carryout approximate analysis of the fresh and dried samples.

Production of flour from the yam chips

Compare flour samples in terms of colour and texture evaluation.