1.1 Introduction
The sweet potato or sweet potato (Ipomoea batatas) is a dicotyledonous plant that belongs to the bindweed or morning glory family, Convolvulaceae. Its large, starchy, sweet-tasting, tuberous roots are a root vegetable (Alkasrawi et al., 2003). The young leaves and shoots are sometimes eaten as greens. The sweet potato is commonly thought to be a type of potato (Solanum tuberosum) but does not belong to the nightshade family, Solanaceae, but both families belong to the same taxonomic order, the Solanales. The sweet potato, especially the orange variety, is often called a "yam" in parts of North America, but is botanically very distinct from true yams.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
Sweet potato (Ipomoea batatas) is an important food crop in the tropical and sub tropical countries and belongs to the family convolvulaceae. It is cultivated in more than 100 countries (Woolfe, 1992). Nigeria is the third largest producer in the world with china leading, followed by Uganda. Sweet potato ranks seventh among the world food crops, third in value of production and fifth in caloric contribution to human diet (Bouwkamp, 1985). Sweet potatoes are rich in dietary fibre, minerals, vitamins and anti oxidants such as phenolic acids, anthocyanins, tocopherol and ß- carotene. Besides acting as anti oxidants, carotenoids and phenolic compounds also provide sweet potatoes with their distinctive flesh colours ( cream, deep yellow, orange and purple). Sweet potato blends with rice, cowpea and plantain in nigerian diets. It is also becoming popular as a substitute to yam and garri. It can be reconstituted into fofoo or blended with other carbohydrate flour sources such as wheat ( Triticum aestivum) and cassava ( Manihot esculenta) for baking bread, biscuits and other confectioneries (Woolfe, 1992).
Cassava flour production till date is carried out at local levels mostly by local women who do so to enhance household food security (Fapojuwe, 2008), and according to Nweke et al. (2002), production of cassava flour remains labour-intensive. Large scale production of cassava flour in Nigeria failed probably due to the limited information on processing variables that promote detoxification in cassava, and fermentation to produce unique flavor characteristics associated with cassava flour (Achinewu and Owuamanam, 2001; Nweke et al., 2002).
Fresh cassava root contains a toxic compound (hydrogen cyanide), which is harmful for human consumption and apparently detrimental for the use of cassava in food industries (Iglesias et al., 2002). However, research have shown that processing techniques such as peeling, fermentation, soaking and drying can detoxify and reduce the cyanide content, improve palatability and add value to the root (Cardoso et al., 2005; Burns et al., 2012). Converting cassava root into food forms and raw materials such as fufu, cassava flour, tapioca, flour, chips and pellets can extend the shelf-life, facilitate trade and promote industrial use (Taiwo, 2006; Fadeyibi, 2012).
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to Evaluate and Optimize the Physiochemical Properties of Composite Flours Made from Wheat Cassava and Orange Flesh Sweet Potato.
1.3 Statement of Problems
Investigation reveals the problems of the Evaluation and Optimization of the Physiochemical Properties of Composite Flours Made from Wheat Cassava and Orange Flesh Sweet Potato research work which entails that, it difficult to understand how cassava and cassava products such as cassava flour can be promoted without giving proper consideration to the fact that it contains cyanogens (linamarin) that liberates poisonous cyanide in the body. Consumption of cassava and its products containing amounts of cyanide can cause acute intoxication, with symptoms of dizziness, headache, nausea, vomiting, stomach pains, diarrhea and sometimes death (Oluwole et al., 2003).
Sweet potato (Ipomoea batatas) is native to the tropical regions in the Americas (Bamforth et al., 1993).Of the approximately 50 genera and more than 1,000 species of Convolvulaceae, I. batatas is the only crop plant of major importance—some others are used locally (e.g., I. aquatica "kangkong"), but many are poisonous. The genus Ipomoea that contains the sweet potato also includes several garden flowers called morning glories, though that term is not usually extended to Ipomoea batatas. Some cultivars of Ipomoea batatas are grown as ornamental plants under the name tuberous morning glory, used in a horticultural context.
1.4 Aim and Objectives of Study
The aim of the study is to Evaluate and Optimize the Physiochemical Properties of Composite Flours Made from Wheat Cassava and Orange Flesh Sweet Potato. In achieving this aim, the following specific objectives were laid out as follows:
- To Evaluate the Composite Flours Made from Wheat Cassava and Orange Flesh Sweet Potato
- To optimize the Physiochemical Properties of Composite Flours Made from Wheat Cassava and Orange Flesh Sweet Potato
- To examine the physico-chemical and functional properties of orange fleshed sweet potato-based composite flours on dry weight basis
- To investigate the effects of processing methods on the physico-chemical properties of sweet potato
1.5 Significance of Study
Cassava, yams (Dioscorea spp.), and sweet potatoes (Ipomoea batatas) are important sources of food in the tropics. The cassava plant gives the third-highest yield of carbohydrates per cultivated area among crop plants, after sugarcane and sugar beets. Cassava plays a particularly important role in agriculture in developing countries, especially in sub-Saharan Africa, because it does well on poor soils and with low rainfall, and because it is a perennial that can be harvested as required. Its wide harvesting window allows it to act as a famine reserve and is invaluable in managing labor schedules. It offers flexibility to resource-poor farmers because it serves as either subsistence or a cash crop (Wikipedia, 2021).
This study will be of immense benefit to other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.6 Scope of Study
The study focuses on the Evaluation and Optimization of the Physiochemical Properties of Composite Flours Made from Wheat Cassava and Orange Flesh Sweet Potato.
1.7 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).
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