Biscuit bars were produced from mixtures of cassava and peanut flours with cornstarch as binder. Box-Behnken response surface design for k=3 was used to study the effects of experimental variables for cassava flour (25- 75%), peanut flour (25-75%) and corn starch (5-15%). Effects of the experimental variables on physicalproperties of the biscuit bars were assessed. Experimental variables had significant effect on the thickness and spread factor of the biscuit bars.


            Biscuits are the major products produced by the biscuit and crackers industries. Flour confectionery describes a large range of flour based goods other than bread manufactured from batter sponge or dough by mixing, kneading and may be created by fermentation, chemical or other means resulting in puff/flaky short or sweet product. Those that have their moisture content reduced to make them exceptionally brittle or crops are generally regarded as biscuits. (Okaka, 1997)
            The word biscuit come from the Latin word Biscuit meaning twice cooked, baking at high temperature followed by drying at lower temperature (Okaka, 1997). The term biscuit and cookie are synonymous. The American Encyclopedia described biscuit as a form of bread baking soda as a raising agent rather than yeast.
            Biscuit are a common feature of southern us cousine which can be served as a side dish with meal or as a breakfast item. Biscuit is also said to be essentially bakery confectionery dried down to low moisture content name derived from Latin word for twice cooked, made from soft flour, mostly rich in fat and sugar and consequently of high energy content of 420 to 510kcal per 100g they are cherished by people of all ages and used at different meals and occasions as part of breakfast, snacks etc. they are eaten with butter and jam or jelly or as a part of a dish called “Biscuit and gravy”. Biscuits are also eaten covered in pizza sauce and cheese. Many varieties exist, both sweet and savoulry often produced in industrial quantities by large food companies. Sweet biscuit are commonly eaten as snack and may contain chocolate fruit, jam or nuts (peanuts). Savoury biscuits are plainer and commonly eaten with cheese following a meal
            The simplest form of biscuit is a mixture of flour and water but may contain fat sugar and other ingredients mixed together into a dough which is rested for a period, passed between rollers to make a sheet. The sheet is then stamped out baked, cooled and packaged. Biscuits are generally made from wheat flour but according to the topic of this project, “use of composite blends for biscuit making”. Some raw materials other than wheat have to be used in producing the flour for the biscuits. In order to get a superior product especially for crackers, the following factors are of importance – choice of flour for sponge and dough, selection of fermentation environment and the baking conditions. It is therefore necessary to search for raw materials that give flour of light quality.
            Biscuits are classified based on their degree of enrichment and processing or by the method adopted in shaping them. Based on the enrichment criterion are hard dough, soft dough and batter biscuit respectively. (Okaka; 1997). Soft wheat is used in making flour for most biscuit and the softness is de to lower protein (gluten) content when compared with the hard wheat. Based on this fact, raw materials are chosen from other legumes such as Peanut and Roots such as cassava. Since they contain protein though in lesser quantity and quality.
            Peanuts are one of the leading agricultural crops of the world and belong to the family leguminous. It is a source of edible oil and plant protein. The characteristic feature of legume seed protein is that they are markedly deficient in methionine and tryptophan. Infact, methioine is t he first limiting essential amino acid in almost all the legume grains. Peanuts contain about 26% to 35% protein with the peanut meal containing a large amount of nutritionally essential amino – acid. The seeds are nutritional and contain vitamin E, Niacin, folacin, calcium, phosphorus, magnesium, zinc, iron, riboflavin, thiamine, potassium etc (Ogbo; 2002). Peanut also contain a significant load of  resveratrol, a strong antioxidant which inhibit lipid peroxidation of low – density lipoprotein (LOL), prevents the cytotoxicity of oxidized (LDL) and protects cells  against lipid peroxidation. Hydrophilic aid lipophilic properties, it can as well provide more effective protection than other well known antioxidations such as vitamin C and E.
Peanut is used for different purposes, food (raw, roasted or b oiled, cooking oil), animal feed and industrial raw material. There are four varieties of peanut:- Virginia, Peruvian runner, Valencia and Spanish.
Cassava, one of the raw materials is an indigenous and stable food of millions of Nigerian people. The few misconceptions related to cassava especially with regard to its low nutritional value and its toxicity have been effectively challenged by National ad International Research Institutions. National Institutions like University of Agriculture Umedike in Umuahia who have succeeded in producing many Tropical Manioc Selection (TMS) varieties with an added advantage of low cyanide.
Despite the obvious advantages of cassava like being easily propagated by stem cutting. Relatively high yielder and excellent source of calories, cassava remained for some time a neglected crop in agricultural research and development activities to an extent not commensurate with its importance as food. However, some developments within the past 15 years have enhanced interest in the crop and research priority has been given to research on its improvement, increased production and utilization.
First, the International Society for Tropical Root and Tubers Crops was founded in 1967 to encourage research, increased production and utilization and exchange of information on tropical root and tuber crops including cassava yams, sweet potatoes and avoids. Second, among the International Institutions (International Institute for Tropical Agriculture – IITA – in Nigeria, and he International Centre for Tropical Agriculture – CIAT in Colombia) that have programmes giving high priority to research on the improvement, production systems, storage and utilization of cassava and other related training.  Roots and Tubers Expansion Programme (RTEP was also put in place to develop and source for alternative uses of cassava as industrial raw material and create enabling market environment. High Quality unfermented flour”, including fortified cassava flours are now more accessible because of the improved processing and technological methods for processing cassava. These technologies can be used to produce particle / whole substitute for wheat flour from 540 100 percent in bakery and confectionery products such as biscuit, chin-chin etc. and some of these snacks have no noticeable change in texture, flavour, aroma nor colour.
The cassava flour is fortified with peanut butter in this project because of its high protein content, vitamins like vitamin E, which is a powerful antioxidant. The manufacture of good biscuit therefore depends mostly on the selection of correct flour for each type ad applying processed which are compatible such processes a re mixing, accretion and fermentation, laminating, baking and cooling (Okaka, 1997:- p. 155).
As everybody including the federal government is putting effort together to induce foreign exchange conservation by means of local material utilization. It has been decided to carryout some work on cassava and peanut blend in order to use them as substitute for imported wheat in making flours for biscuit manufacture. Peanut butter is also added to complement the necessary amino acids.
The result of research carried out and test conducted by Roots and Tubers Expansion Programme show that it is possible to produce acceptable biscuits of comparable standard to that of wheat flour biscuits using composite flours from the above named legume and Roots.
Wheat whose flour is the major material used for biscuit manufactures in most countries of the world traditionally employ wheat for biscuits and similar products. Although wheat flour is generally employed as the basic ingredients in biscuit manufacture. Wheat is uniformly grown all over the world and being a temperature crop, it only grows under certain climatic conditions. Consequently, biscuit manufacture industries in countries where wheat does not grow have to import the grain or the flour.
In countries, Nigeria, to be precise, wheat is cultivated though not in appreciable quantity due to climate conditions, a large sum of foreign exchange is spent on importation especially with the present rate of growth of biscuit and allied industries in Nigeria (Federal Office of Statistics, Lagos Nigeria). There are a lot of industries (confectionery) although the date is not yet readily available, all based on wheat flour. Foreign exchange spend as at 1982 are huge amount of money. Therefore success in this trend of supplementation will save a huge sum of money being spend annually on wheat importation and could now be utilized to improve other sector of the country’s economy.
The aim of this project work therefore is to reduce or stop totally the extensive importation of wheat, thereby broaden the food base of Nigerians. The commercial and industrial implication will bring economic benefits to all biscuit consumers by making the product more readily available. Supplementation of imported wheat flour with cassava flour will save millions of naira in foreign exchange.
It is also estimated that the use of these composite blends (cassava flour and peanut butter) will result in the production of biscuits that are less expensive and highly nutritive than those produced before.
It will also create new employment opportunities as well as economic self-reliance both at the industrial and house – hold level of cassava processors.

1.4 Justification 

For many years Nigeria has been relying on importation of wheat and wheat flour for its bakery industry. Such importations have led to high production costs for baked products, resulting in skyrocketing retail prices of baked products making the majority of the rural communities unable to purchase such products. Past research has demonstrated that cassava and peanut flours can be partially substituted for wheat flour in the baking of bread and biscuit. This offers great opportunity to reduce overreliance on wheat flour as the only raw material for bread and cookie making, and also should reduce retail prices of baked products. Cassava and peanuts are the potential crops to be evaluated for blending with wheat flour for products with increased baking qualities, human nutrition and reduced costs of production. 
The targeted crops for blending with wheat flour are adaptable and largely produced in Nigeria.  As a result, import costs for raw materials will be significantly reduced. In general, utilization of cassava and peanut flours will reduce overreliance on wheat flour and result in nutritious products affordable to the rural masses, hence improving both Nigeriaan nutrition and the national economy.

Evaluation of the physicochemical and baking qualities of baked wheat products supplemented with cassava and peanut flours is a major step in facilitating utilization of the flours in baking. Knowledge of these characteristics will enhance utilization of the flours in bread and cookie making. Successful results from the study will be extended to the rural communities so that they can have skills on standalone ability to make breads and biscuit from locally available raw materials. The main aim of the study, therefore, was to evaluate the physicochemical properties and baking qualities of bread and cookie samples made from wheat-cassava-peanut flour blends as compared to non-blended wheat flour (control).

For more Food Science & Technology Projects click here
Item Type: Project Material  |  Attribute: 48 pages  |  Chapters: 1-5
Format: MS Word  |  Price: N3,000  |  Delivery: Within 30Mins.


No comments:

Post a Comment

Select Your Department

Featured Post

Reporting and discussing your findings

This page deals with the central part of the thesis, where you present the data that forms the basis of your investigation, shaped by the...