Starch is the major component of the cassava root and its use is primarily determined by its physicochemical properties (Onitilo et al 2007). Cassava starch is processed into various pregelatinised instant and convenience foods which include gari, pupuru, fermented cassava flour, and fufu. All these differ in their pasting characteristics, which are determined by the varieties of cassava and the processing methods employed (Sanni et al 2003, Onitilo et al 2007, Etundaiye et al 2009).
Yam flour (elubo) is produced from washed and peeled yam tubers that are; chipped, blanched, dried and milled. Yam flour is used in the preparation of a stiff porridge locally called Amala. Though an important staple food in western Nigeria, yam flour is more expensive than other locally produced flours which restricts its co sumption to the middle and high income groups. There is high consumer preference for yam flour because of its hydration capacity, gruel gel strength, resistance to syneresis and good sensory characteristics.
Cassava flour (Lafun in local parlance) is a cheaper alternative but is poor in protein with its amino acid profile indicating a limitation in sulphur containing amino acids(1). It is desirable to enrich lafun in order to improve its nutritional qualities. Lafun can be supplemented with a wide variety of other foods including cereals.
Grain sorghum (Sorghum bicolor), which is one of the important cereal crops of Nigeria, is grown in abundance (2). Sorghum forms one of the main staples in the diet of low income families. In Nigeria, the main uses of sorghum are in weaning diets for children, served as a breakfast cereal, or as a main meal for adults, snackfoods and alcoholic and non alcoholic beverages (3,4). Although sorghum protein is limiting in lysine and total Sulphur containing amino acids (5).
1.2 Problem statement
Yam flour used in the preparation of a stiff porridge locally called Amala which is an important staple food in western Nigeria, us more expensive than other locally produced flours which restricts its consumption to the muddle and high income groups. This has made consumers that cannot afford yam flour source for alternative low cost flour such as sorghum-cassave flour. Hence there is need to evaluate sorghum-cassava flour as a substitute for traditional Nigerian Yam flour (elubo).
1.3 Objectives of the study
The major objective of the study is to evaluate sorghum-cassava flour as a substitute for traditional Nigerian yam flour (elubo). This is to be achieved through the following specific objectives:
(i) The proximate composition of the flour and,
(ii) The physiochemical properties of the flour
(1) what is yam flour(elubo), Cassava flour and sorghum flour?
(2) what are their economic importance?
(3) why do consumers try to substitute sorghum -cassava flour for traditional Nigerian yam flour(elubo).
1.5 Significance of the study
1.6 Scope of the study
The research focuses on the evaluation of Sorghum- cassava flour as a substitute for traditional Nigerian Yam flour (elubo).
FAO (1990) Roots, Tubers, Plantains and Bananas in Human Nutrition. Food and Agric-culture organisation of the United Nations, Nutritional studies. No.24, Rome, Italy 85,pp37-58.
FAO (1995) Sorghum and Millets in Human Nutrition. Food and Agriculture organization of the United Nations, Rome. Italy.
Adeyemi IA(1998) Technological Options for weaning Food Manufacture in Nigeria. Paper presented at the International seminar on Development of Infant and Weaning Foods based on Cereals and Legumes. Institute Technologies Allimentaire, Dakar, Senegal. 5th-8th December, 1988.
Sanni AI, Onilude AA, Ibidapo OT (1999) Biochemical composition of infant weaning food fabricated from fermented blends of cereal and soybean. Food chem 65(1): 35-39
FAO (1970) Amino Acid content of Foods and Biological Data on Proteins. Foods and Agriculture Organization of the United Nations, Rome, Italy.
Etydaiye, H.A Nwabueze, T.U and Sanni, L.O.,(2009). Quality of fufu processed from cassava mosaic disease (CMD) and resistant varieties. Africa. J. Food Sci. 3(3):61-67
Onitilo M.O, Sanni L.O, Daniel I, Maziyadixon, B and Dixon A.(2007). Physiochemical and functional properties of native starches from cassava varieties in south west Nigeria. J. Food, Agric Environ 5(3&4):108-114.
Sanni L.O., Onitilo, M.,Oyewole, O.B., Dipeolu, A.O., Adebayo K. Ayinde I.A. Tomlin’s, K and Wesby A. (2003). Effect of cassava varieties and processing methods on the qualities of starch in Southwest Nigeria. Paper presented at the Food Africa, Yaounde, Cameroon, 2003).