In ternationa l Scholars Journa ls African Journal of Food Science Research ISSN 2375-0723 Vol. 6 (2), pp. 255-262, February, 2018. Available online at www.internationalscholarsjournals.org © International Scholars Journals Author(s) retain the copyright of this article. Full Length Research Paper A study of the nutritional composition of complementary foods micronutrients improved cassava varieties O. O. Onabanjo 1, 2 *, C. R. B. Oguntona 1 , Bussie Maziya-Dixon 2 , I. O. Olayiwola 1 , E. B. Oguntona 3 and A. G. O. Dixon 2 1 Department of Nutrition and Dietetics, University of Agriculture, Abeokuta, Ogun State, Nigeria, 2 International Institute of Tropical Agriculture, Ibadan, Oyo State, Nigeria, 3 Department of Animal Nutrition, University of Agriculture, Abeokuta, Ogun State, Nigeria. Accepted 24 August, 2017 Complementary foods were formulated and their nutritional composition analyzed from three yellow and one white cassava varieties. The composites were analyzed for proximate, mineral, fatty acids and amino acids. The mean values for the proximate composition of the diets are moisture (41.4 g kg -1 ) wet weight, ash (47.4 g kg -1 ), crude protein (145.8 g kg -1 ), crude fat (106.7 g kg -1 ), crude fiber (21.1 g kg -1 ), total carbohydrate (633.5 g kg -1 ), and energy (409.2 kcal) . The diets supplied adequate amounts of most minerals, except iron (about 65% of the standard). The composites contained all the essential amino acids with adequate chemical score for most amino acids. The complementary diets contained moderate to high proportions of -linolenic acids (18:3n3) and a high proportion of linoleic acid (18:2n6), which resulted in a high total n-6/total n-3 ratio and a high linoleic/ -linolenic acids ratio. Micronutrient improved cassava varieties can be effectively used to formulate complementary food as acceptable micronutrients supplement. Key words: micronutrient-improved, cassava, complementary foods, children. INTRODUCTION Childhood malnutrition is widely prevalent in many parts of the world, particularly in the developing countries like Nigeria (UNICEF, 2006). Protein, energy and micronutrient malnutrition are the commonest form. The period from birth to 2 years of age is a critical period for the promotion of optimal growth, health, and behavioral development. Studies in Nigeria have indicated a high prevalence of malnutrition among under-five children of which inappropriate breastfeeding and complementary feeding practices coupled with high rates of infectious diseases are the principal proximate causes of malnutrition during the first two years of life (NFCNS, 2003; NDHS, 2003). Breast milk is the perfect food for the infant during the first 6 months of life (UNICEF, 2006), because it contains all the nutrients and immunological factors an infant requires to maintain optimal health and growth. However, at about 6 months, the supply of energy and some nutrients from breast milk is no longer adequate to meet *Corresponding author. E-mail: oonabanjo@cgiar.org. an infant’s needs, hence, need for complementary food (WHO/UNICEF, 1998; Dewey, 2003; Dewey and Brown, 2003). The amount of nutrients required from complementary foods depends on the quantity provided by human milk and varies markedly by nutrient, ranging from nearly 100% for iron to 0% for vitamin C. The calculation of the nutrients required from complementary foods is based on the recommended intake for each nutrient minus the amount of the nutrient consumed daily from human milk (WHO/UNICEF, 1998; Dewey and Brown, 2003). The adequacy of complementary diet to meet nutrient requirements depends on the nutrient content of foodstuff used in the formulation. The food-based dietary guideline for Nigeria has recommended the use of available foodstuff in various communities and home levels to prepare nutritious diets for infants and children. Cassava, soybean, groundnut and carrot are readily available foods in Nigeria. They have promising nutritional attributes. Cassava is one of such staples with potential to meet this requirement, especially in the sub-Saharan Africa. The importance of cassava to the livelihoods of many millions of poor people has made the commodity a target Onabanjo et. al. 256 for interventions. New Partnership for Africa Development (NEPAD) has adopted the slogan “Cassava: A Powerful Poverty Fighter in Africa” for its Pan-African Cassava Initiative. The normal white tubers contain only small amounts of -carotene (Bradbury and Holloway, 1998), but yellow cassava contains up to about 100 times as much (McDowell and Oduro, 1993). In addition, cassava leaves are good sources of -carotene and are consumed as vegetables in many parts of the Third World, especially in the Democratic Republic of Congo, and Senegal. Cassava could be a vehicle for delivering micronutrient- rich food to alleviate deficiencies. Use of multimix might help to ensure nutrition security in infants and young children. The nutrient potentials of the food (cassava, soybean, groundnut and carrot) make it imperative that scientific studies be made on their composite for possible use as complementary food. The purpose of the study was to formulate and analyze the nutritional composition of complementary foods micronutrients improved (3 yellow and one fleshed) cassava varieties. MATERIALS AND METHODS Characteristics of raw ingredients Cassava roots and leaves (Manihot esculenta), soybean (Glycine max.), groundnut (Arachis hypogaea), and carrot (Daucus carota) were used to formulate four composite diets. The cassava roots and leaves, and soybean were obtained from the experimental fields of the International Institute of Tropical Agriculture, (IITA) Ibadan, Nigeria. Groundnut and carrot were purchased from local markets in Ibadan. Cassava roots were peeled manually with a stainless steel knife, washed thoroughly with potable water to remove all dirt and adhering sand particles. The roots were then grated into mash using a stainless steel grater driven by a petrol engine, packed into Hessian sacks, and dewatered immediately using a hydraulic press to express liquid from the mash as well as to prevent fermentation. The mash was then sieved manually with a stainless steel sieve to pulverize the pressed cake and separate fibrous materials. The resulting flour was dried in an oven dryer at 40 0 C, and milled using a stainless steel milling machine before being packaged into polyethylene bags and stored at a cool dry room at -20 0 C. Soybean and groundnut were cleaned and roasted in a preheated stainless steel pot on an electric stove for 15 min. The roasted seeds were dehulled manually by rubbing gently with hand and winnowed to remove the hulls. The dehulled seeds were then ground into fine flour with a domestic grinding machine. Cassava leaf flour was obtained by washing fresh leaves and pressing them between the palms to remove excess water. The leaves were heat- treated in an empty dry pot, placed over a source of heat. The leaves were tossed constantly with a wooden spoon to ensure even distribution of heat for 5 min. The heat–treated leaves were pounded in a wooden mortar for 30 min. The pounded leaves were put in twice their weight of water, gradually brought to a boil, and cooked for 1 h 30 min. The processed leaves were dried at 60 0 C for 48 h, milled, and stored in air-tight zip-lock bags until analysis (Bokanga, 1994). The carrot powder was obtained by washing the carrot roots with water and then slicing and drying them at 40 0 C, and milling them into flour with a stainless steel milling machine. Lastly, the processed food commodities were analyzed for their chemical proximate and mineral composition, fatty and amino acids profile and diets formulated based on the WHO/FAO Codex standard (FAO/WHO, 1991). Formulation of composite flours The composite flours were formulated by blending all the ingredients in different proportions using the Owl Tech Wizard Software TM , Version 3 to develop and optimize the different formulations. The composite flours of the four complementary foods were formulated based on the optimization given by the software as follows: Diet 1: Cassava root (variety 01/1371), 67%: soybean, 14.7%: groundnut, 10.5%: cassava leaves, 5.3%: carrot, 2.5% (w/w). Diet 2: Cassava root (variety 01/1235), 67.6%: soybean, 13.5%: groundnut, 10.5%: cassava leaves, 5.7%: carrot, 2.7% (w/w). Diet 3: Cassava root (variety 94/0006), 67.7%: soybean, 14.1%: groundnut, 9.7%: cassava leaves, 5.7%: carrot, 1.8% (w/w). Diet 4: Cassava root (variety TME 1), 68.9%: soybean, 13.8%: groundnut, 9.3%: cassava leaves, 5.7%: carrot, 2.3% (w/w). Chemical analysis The composite flours were analyzed for their proximate composition, minerals, amino acids, and fatty acids profile to ascertain their conformity with the standards. Proximate composition Standard procedures (AOAC, 2005) were used to determine the moisture content, crude fat, fibre and ash content, crude protein (N * 6.25) by (HACH, 1990), and total carbohydrate (Dubois et al., 1956) from total starch and sugar. Energy value was calculated using the Atwater’s conversion factors, protein and carbohydrate (4 kcal/g) and fat (9 kcal/g). Methods validation The accuracy of the concentrations determined in this study was checked by measurements of the reference materials SRM no. 2383 Baby Food Composite from the National Institute of Standards and Technology of the Department of Commerce, United States of America. Amino acid analysis Amino acids composition was quantified after hydrolysis with HPLC in reversed-phase column, after a derivatization with 9- fluorentylmethyl chloroformate and a fluorescence detector at the Irene Analytical Services, South Africa (AOAC, 2005). The concentration of the individual amino acid was calculated in relation to the protein content. Chemical score was calculated as follows using egg as the reference protein. Chemical score = mg amino acid in 1g of test protein × 100 mg amino acid in 1g of reference protein Fatty acid analysis Fatty acids were separated and quantified using a Hewlett-Packard gas chromatograph equipped with HP Chemstation software (6890 Series II) after extraction with chloroform: methanol (2:1, v/v) as described by (Christopherson and Glass, 1969). 257 Afr. J. Food Sci. Res. Table 1. Proximate composition of the composite diets g kg -1 dry weight* Nutrients Diet 1 Diet 2 Diet 3 Diet 4 Yellow White Moisture 41.7± 0.14 40.5± 0.07 42.1± 0.02 41.1± 0.13 Ash 50.2± 0.07 49.4± 0.22 44.4± 0.08 45.4± 0.06 Crude protein 147.7± 0.22 145.6± 0.38 145.0± 1.02 145.0± 0.86 Crude fat 108.9± 0.57 107.0± 0.21 106.7± 0.08 104.1± 0.33 Fiber 21.0± 0.08 21.7± 0.11 20.1± 1.01 21.7± 0.88 Sugars 62.2± 0.54 58.9± 0.22 61.0± 1.09 46.5± 0.76 Starch 581.3± 1.31 600.1± 0.21 558.7± 0.97 577.9± 0.54 Total Carbohydrate 643.5± 1.80 658.9± 2.17 619.7± 1.17 624.4± 1.11 Energy (kJ) 414500±12.33 418900± 11.10 401900± 9.44 401500± 14.11 *Values are means ± SD for three determinations Complementary foods, Diet 1 (cassava variety 01/1371), 2 (variety 01/1235), 3 (variety 94/0006), 4 (variety TME 1) Table 2. Mineral contents (mg kg -1 )) of the diets. Mineral Diet 1 Diet 2 Diet 3 Diet 4 (mg kg -1 ) Yellow White Iron 75.4 73.8 74.2 73.9 Zinc 63.0 62.6 62.2 62.0 Manganese 29.0 28.0 27.0 27.0 Copper 89.0 87.0 87.0 90.0 Calcium 2700.0 2480.0 2380.0 2510.0 Boron 13.0 13.0 14.0 13.0 Molybdenum 0.8 0.9 0.9 1.0 Cobalt 0.2 0.2 0.2 0.2 Nickel 1.9 1.7 1.7 2.0 Magnesium 1490.0 1490.0 1440.0 1470.0 Sodium 210.0 230.0 168.0 210.0 Potassium 9100.0 9000.0 8600.0 8600.0 Phosphorus 2400.0 2500.0 2600.0 2600.0 Silicon 1480.0 1480.0 1490.0 1460.0 Aluminium 10.0 1.4 9.0 1.1 Titanium 0.6 0.7 0.6 0.6 Chromium 0.0 0.0 0.0 0.0 Cadmium 0.1 0.1 0.1 0.1 Lead 1.0 1.0 1.0 1.0 Selenium 4.0 4.0 4.0 4.0 Analysis of minerals The minerals were determined at Waite Analytical Services. School of Agriculture and Wine, University of Adelaide, Australia using an Inductively Coupled Plasma Atomic Emission Spectrometry (AOAC, 2005) (ICPAES) made in Switzerland by ARL model 3580 B. Replicates of three samples were analyzed to check on the accuracy and reproducibility of the method. RESULTS The proximate compositions of the diets are presented in Table 1. The mean compositions are moisture (41.4 g kg -1 ), ash (47.4 g kg -1 ), crude protein (145.8 g kg -1 ), crude fat (106.7 g kg -1 ), crude fibre (21.1 g kg -1 ), total carbohydrate (633.5 g kg -1 ), and energy (409.2 kcal). The mineral compositions of the four diets are presented in Table 2. The iron, zinc and calcium contents of the flours ranged from 73.8 - 75.4 mg, 62.0 - 63.0 mg and 2380 – 2700 mg per kg dry flours respectively. The flours supplied adequate amounts of most minerals except for iron and zinc contents, which supplied about 65 and 67% of the Codex standard (FAO/WHO, 1991) respectively. Again, a dry weight of 65 g of the composite flours were calculated and compared to recommended dietary allowances (RDA) for the same age groups (Dewey, 2001). The comparison result is presented in Table 3. All the four complementary foods were found to provide more than adequate intake levels of Selenium (4 mg/kg/day) and magnesium (957.1 mg/kg/day), and relatively low amounts of Calcium (1636 mg/kg/day), Iron (48.31 mg/kg/day), and Zinc (40.59 mg/kg/day). The composites contained all the essential amino acids (Table 4). The comparison of the essential amino acids to the FAO reference values (WHO/FAO, 1985), and percentage chemical score are presented in Table 5. The complementary foods contained higher chemical scores of most essential amino acids. The chemical score ranged from 37.7% in formula 4 for methionine to 310% in formula 1 for leucine. Six (6) of the essential amino acids, Leucine, Lysine, Phenylalanine, Threonine, Tyrosine and Valine, met the FAO/WHO reference values in all the diets. The fatty acids compositions of the diets are presented in Table 6. The four diets contained all the fatty acids between Tetradecanoic acid Tetracosanoic acid (C-14 to C-24) with the exception of Hexanoic acid (C-6) through Tridecanoic acid (C-13), Pentadecanoic acid (C-15), and Nicodecanoic acid (C-21). Odd-chain fatty acids, such as Heptadecanoic acid (C- 17:0) and 10- heptadecenoic acid (C- 17:1), were present in very small concentrations, varying from 0.4 g kg -1 of total fatty acids to 1.1 g kg -1 . Compared with the WHO recommendation Onabanjo et. al. 258 Table 3. Daily consumption of the four complementary diets compared to the recommended daily allowance. Mineral Diet 1 Diet 2 Diet 3 Diet 4 Mean RDA † (6-11 (mg kg -1 /day) Yellow White months) Iron 49.01 47.97 48.23 48.035 48.31 90.0 * Zinc 40.95 40.69 40.43 40.30 40.59 41.0 *† Manganese 18.85 18.20 17.55 17.55 18.04 Copper 57.85 56.55 56.55 58.50 57.36 Calcium 1755.00 1612.00 1547.00 1631.50 1636.00 4000.0 Boron 8.45 8.45 9.10 8.45 8.61 Molybdenum 0.52 0.59 0.59 0.65 0.59 Cobalt 0.13 0.13 0.13 0.13 0.13 Nickel 1.24 1.11 1.11 1.30 1.19 Magnesium 968.50 968.50 936.00 955.50 957.10 530.0 Sodium 136.50 149.50 109.20 136.50 132.90 Potassium 5915.00 5850.00 5590.00 5590.00 5736.00 Phosphorus 1560.00 1625.00 1690.00 1690.00 1641.00 Silicon 962.00 962.00 968.50 949.00 960.40 Aluminium 6.50 9.10 5.85 0.72 5.54 Titanium 0.39 0.46 0.39 0.39 0.41 Chromium 0.00 0.00 0.00 0.00 0.00 Cadmium 0.07 0.07 0.07 0.07 0.07 Lead 0.65 0.65 0.65 0.65 0.65 Selenium 2.60 2.60 2.60 2.60 2.60 1.00 † FAO/WHO (2002). * RDA, assuming a moderate bioavailability of 10% iron absorption. *† RDA, assuming a moderate bioavailability. Table 4. Amino acid composition of the diets (g kg -1 protein). Amino acids FAO/WHO Diet 1 Diet 2 Diet 3 Diet 4 reference.protein* Yellow White Isoleucine 42 40.0 38.4 39.5 41.4 Leucine 42 130.2 72.9 71.9 72.7 Lysine 42 65.4 61.4 64.1 62.6 Methionine 22 10.6 11.5 10.2 8.3 Phenylalanine 28 50.1 50.5 50.3 50.8 Threonine 28 35.3 35.8 35.9 36.1 Valine 42 46.5 46.1 47.3 48.5 Tryptophan 14 8.8 12.8 12.0 13.6 Alanine 45.9 44.8 45.5 47.3 Arginine 106.0 108.1 108.4 109.9 Aspatatic acid 111.9 113.2 11.08 114.1 Cysteine 20 11.2 9.0 9.0 08.9 Glutamic acid 177.3 181.7 179.1 178.5 Glycine 47.7 48.6 46.7 48.5 Histidine 37.1 27.5 33.0 26.0 Proline 48.3 48.6 48.5 47.9 Serine 44.8 47.3 45.5 44.9 Tyrosine 28 41.8 41.6 41.9 40.2 * (FAO/WHO, 1985) 259 Afr. J. Food Sci. Res. Table 5. Percentage chemical scores of the essential amino acids in the diets. Amino acid Diet 1 Diet 2 Diet 3 Diet 4 Yellow White Isoleucine 95.2 91.4 94.0 98.6 Leucine 310.0 173.6 171.2 173.1 Lysine 155.7 146.2 152.6 149.0 Methionine 48.2 52.3 46.4 37.7 Phenylalanine 178.9 180.4 179.6 181.4 Threonine 126.1 127.9 128.2 128.9 Valine 110.7 109.8 112.6 115.5 Tryptophan 62.9 91.4 85.7 97.1 Table 6. Fatty acids composition of complementary diets as g kg -1 total fatty acids. Fatty acid Diet 1 Diet 2 Diet 3 Diet 4 Yellow White Saturated fatty acid Tetradecanoic acid (14:0) 0.7 0.5 0.4 0.4 Hexadecanoic acid (16:0) 97.3 97.2 97.7 98.1 Heptadecanoic acid (17:0) 1.0 0.9 0.9 1.1 Octadecanoic acid (18:0) 0.6 29.8 30.3 30.2 Eicosanoic acid (20:0) 13.1 13.1 13.7 13.3 Docosanoic acid (22:0) 0.6 20.5 20.8 21.0 Tetracosanoic acid (24:0) 1.6 11.4 11.7 11.6 Monosaturated fatty acids 9-tetradecenoic acid (16:1) 0.7 0.6 0.6 0.7 10-heptadecenoic acid (17:1) 0.4 0.4 0.5 0.4 9- octadecenoic acid (18:1) 529.0 518.7 512.9 515.8 11-eicosenoic acid (20:1) 10.0 9.8 9.9 9.7 13-docosenoic acid (22:1) 0.6 0.6 0.6 0.6 Polyunsaturated fatty acids 9,12-octadecadienoic acid (18:2) 270.6 282.2 285.9 283.2 9,12,15-octadecatrienoic acid (18:3) 12.5 13.3 13.2 13.0 9,12,15-eicodecatrienoic acid (20:3) 0.6 0.7 0.6 0.6 9,12,15,18-eicodecatetranoic acid (20:4) 0.4 0.5 0.6 0.4 diets contained moderate (12.5 - 13.3 g kg -1 ) to high proportions of -linolenic acids (18:3n3) and high proportion of linoleic acid (18:2n6), which resulted in a high total n-6/total n-3 ratio and a high linoleic/ -linolenic acids ratio (20.10 - 22.10) (Table 7). DISCUSSION In assessing the overall nutritive intake of infants, the combined composition of the breast milk and complementary food needs to be taken into consideration. Some nutrients, such as fatty acids, are abundant in breast milk. However, low concentrations of other nutrients, such as iron, calcium, and zinc, may lead to clinically significant deficiencies if without supplementation (FAO/WHO, 1995). Also, the recommendation of the World Health Organization that children should be exclusively breastfed until 6 months, with introduction of complementary foods and continued breastfeeding thereafter (FAO/WHO/UNU, 1985), was considered in analyzing the nutritional value of the complementary foods. The potential disadvantages of fiber in foods for infants and young children are an important nutritional issue (Jansen, 1980). Possible undesirable aspects of high fiber levels in weaning foods include increased bulk and lower caloric density, irritation of the gut mucosa, and Onabanjo et. al. 260 Table 7. Fatty acid composition (g kg -1 wt/wt) of the complementary diets compare to WHO recommendations. Fatty acid Diet 1 Diet 2 Diet 3 Diet 4 Recommended † Yellow White Linoleic acid 18:2n-6 270.6 283.2 110-120 282.2 285.9 - Linolenic acid 18:3n-3 12.5 13.3 13.2 13.0 8-9 Arachidonic acid 20:4n-6 0.4 00.5 0.6 0.4 5-6 Total unsaturated 824.8 826.8 824.8 824.4 448-524 Total saturated 174.9 173.4 175.5 175.7 452-535 Unsaturated/saturated ratio 5:10 5:10 5:10 5:10 0.84:1-1.16:1 18:2n-6/18:3n-3 ratio 20:10 21:10 22:10 22:10 5:1-10:1 Total n-6/total n-3 ratio 22:10 22:10 22:10 22:10 2.4:1-2.7:1 † Recommended data from Koletzko et al. (1992). Medians calculated from average FA values reported of human milk in Europe and Africa. Ratio of 18:0 to 18:3 as suggested by the FAO/WHO Joint Consultation, 1995. adverse effects on the efficiency of absorption of various nutrients of significance in diets with marginal nutrient content. A maximum level of 5% of fiber for infants and young children is set by the FAO/WHO/UNU Codex standards (FAO/WHO, 1998). Children should have lower dietary fiber intakes than adults, with the recommended amount proportional to body weight (Hegazy et al., 1989). The fat content of the complementary foods was within the FAO/WHO Codex standard (FAO/WHO, 1991). This could be attributed to the inclusion of soybean and groundnut in the blends, and tends to agree with the recommendations (FAO/WHO, 1998), that vegetable oils be added in foods meant for infants and children. This will not only increase the energy density but also be a transport vehicle for fat soluble vitamins. Brown et al. (1998) have concluded that infants aged 6 - 8 months who are consuming an average amount of breast milk/day (674 g/day) do not need the dietary supplementation of fatty acids to achieve 30% of the daily intake. If the breast milk has a low fat concentration, as may happen in developing countries, infants require an additional 10 - 24% of the energy from fat. By the time infants reach 9 months of age, their complementary food diet should provide 13% of the energy from fat (Dewey and Brown, 2003) . The four complementary formulas supply appreciable quantities of fat to the blends. The fat can also provide essential fatty acids, such as n-3 and n- 6 Polyunsaturated Fatty Acids (PUFA), needed to ensure proper neural development. Fatty acids, especially the essential ones (EFA), - linolenic acid and linoleic acid, are precursors to docosahexaenoic acid and arachidonic acid that are critical for growth and development, particularly of the nervous system in the first 6 months of life (Salem et al., 1996). Both are necessary components of myelin, synaptic cell membranes, and photoreceptor cells. The report of WHO on complementary feeding concludes that diets low in fat may be adequate, as long as the minimum requirements for EFA are met (Brown et al., 1998). Fernandez et al. (2002), and his colleagues also were of the same opinion, as the findings of their study on the fatty acid composition of Nigerian weaning foods revealed that the foods were devoid of arachidonic and decosahexanoic acids, but high in linoleic and linolenic acids. The linoleic acid to - linolenic acid ratio observed in this study is higher than the recommendation. The concern is that the relatively high levels of linoleic acid might inhibit the synthesis of docosahexaenoic acid from -linolenic acid (Ballabriga, 1994). The energy values of the complementary foods are in accordance with the recommendations of FAO/WHO/UNU (1985), which specify 1000 kJ/g (1.0 kcal/g) as safe for small children aged 2 to 5 years. The Food and Agriculture Organization and the World Health Organization (FAO/WHO, 1998) have also recommended that foods fed to infants and children should be energy- dense. This, according to the recommendation, is necessary because low energy intake foods tend to limit total energy intake and the utilization of other nutrients. This suggests that infants may not have to consume larger quantities of the formulas to meet their energy needs. The requirements for the maintenance of body protein equilibrium as well as the optimum pattern of individual essential amino acids change little between the ages of 6 and 24 months (Reeds and Garlick, 2003). According to the Codex standard, the amounts of protein that should be supplied by complementary foods are between 60 and 110 g kg -1 of dry food. The protein values in this study agrees with the recommended values of the Codex standard, meaning that all the formulas provide adequate levels of protein for a child who consumes an average amount of breast milk. These values are slightly below the recommendation of the FAO/WHO/UNU (1985), which recommends a minimum protein content of 261 Afr. J. Food Sci. Res. 150 g kg -1 dry weight. Both soybean and groundnut have been recommended for infant feeding (Badamosi et al., 1995; Temple et al., 1996; Gibson et al., 1998; Nnam , 2002) due to their positive contribution to protein nutrition levels. The amino acid content of complementary foods is a particularly relevant issue in infant feeding, where Protein-Energy Malnutrition (PEM) has continued to pose challenges in developing countries. This, according to other researchers, is due to poor feeding practices and the low quality protein commonly associated with plant- based single diets (Badamosi et al., 1995; Temple et al., 1996). All the essential amino acids were present in the complementary foods, but quite a number did not meet the FAO/WHO reference values. A lower score for any of the essential amino acids designates the limiting characteristics of the amino acid and gives an indication of the protein quality. Complementary foods are important sources of micronutrients for developing infants. Iron, Zinc, Phosphorus, Magnesium, and Calcium have been identified as problem nutrients from six months of age and must be supplemented by the addition of complementary food (Brown et al., 1998). According to Brown and co-workers (WHO, 1998), breast milk can adequately supply the nutrients need of infants 9 to 11 months old for vitamin C, folate and B12. In contrast, complementary foods should provide approximately 12% of the vitamin A, 25% to 50% of the Cu, riboflavin, 50% to 75% of thiamin, Mn, and 75% to 100% of niacin, Zn and Fe, assuming an average composition and intake of breast milk, meaning that the composition of these micronutrient is low in human breast milk. The Calcium, Zinc, Copper, Magnesium, and Phosphorus contents of the four complementary foods are adequate to meet the needs of children aged 6 to 23 months. This supported the findings (Bond et al., 2005). However, the Iron standards were not met, although about 65% of the FAO/WHO Codex standards were supplied (FAO/WHO, 1991). These local complementary foods would have to be further fortified with iron to adequately complement breast milk. The absorption and utilization of the iron and zinc in complementary foods which contain plant materials are significantly lower than in those from animal sources. The bioavailability of non-heme iron found in plant sources is 2 - 8%, compared to 25% bioavailability of heme iron found in animal products (Brown et al., 1998). Phytic acid is a potential inhibitor of both iron and zinc in plant food materials. It affects the bioavailability of minerals by forming an insoluble complex with the metals of Iron, Zinc, and Calcium, inhibiting their absorption (Gibson et al., 1998). The inhibitory effect of phytic acid on Zinc absorption is notably dose-dependent (Sandstrom and Lonnerdal, 1989). Hence, any strategies that reduce the phytic acid content of these complementary foods might markedly enhance Zinc bioavailability and simultaneously increase absorption of non-heme Iron and calcium to some extent. The bioavailability of non-heme Iron or Zinc can also be improved by enriching the complementary foods with sources of absorption enhancers such as ascorbic acid (for non-heme Iron), other organic acids and cellular animal protein (for non-heme Iron and Zinc), and fat (for retinol and provitamin A carotenoids). These enhancers can be added in the form of fresh fruits (citrus fruits), vegetables (tomatoes, green leaves), legumes (groundnut flour) or small amounts of meat, poultry, or fish (perhaps as dried flours) and their inclusion in complementary foods should be encouraged (Gibson et al., 1998). From this study, it would be concluded that utilization of micronutrients improved cassava varieties particularly to formulate complementary food in various cassava agro- ecologies in the region will contribute to an increase in the intake of micronutrients and hence help in combating deficiencies, primarily of Iron, Calcium, and Zinc. 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