Potential Use of Okra Seed (Abelmoschus esculentus Moench) Flour for Food Fortification and Effects of Processing

CHAPTER

19

Potential Use of Okra Seed (Abelmoschus esculentus Moench) Flour for Food Fortification and Effects of Processing Oluyemisi Elizabeth Adelakun1, 2, Olusegun James Oyelade1 1 Department of Food Science and Engineering, Ladoke Akintola University of Technology, Ogbomoso, Oyo State, Nigeria 2 Biocatalysis and Technical Biology Research Building, Cape Peninsula University of Technology, Bellville, Cape Town, South Africa 205

CHAPTER OUTLINE Introduction 205 Bread Fortification with Okra Flour 206 Cereal-Based Food Fortification with Okra Flour 207 Okra Flour as Supplement in Infant-Weaning Foods 209

Technological Issues 210 Conclusion 211 Summary Points 211 References 211

INTRODUCTION Macro- and micronutrient malnutrition has worldwide endemic potential because of its impacts both in developing nations and in the industrialized regions of the world. Systemic malnutrition is increasingly becoming a serious threat to human health because it is a major risk factor for many diseases and it contributes to morbidity and even mortality. One way to curb the global problem is through food fortification of plant origin. Food fortification is broadly aimed at allowing people to obtain from their diet all the energy, including macroand micronutrients, they need to enjoy healthy and productive lives (Allan et al., 2006; Aminigo and Akingbala, 2004). Most food fortification programs are targeted to augment levels of essential nutrients required in the diet, including protein and micronutrients such as iron, vitamin A, iodine, zinc, folate Flour and Breads and their Fortification in Health and Disease Prevention. DOI: 10.1016/B978-0-12-380886-8.10019-4 Copyright Ó 2011 Elsevier Inc. All rights reserved.

SECTION 1 Flour and Breads

(vitamin B9), cobalamin (vitamin B12), thiamine (vitamin B1), riboflavin (vitamin B12), niacin (vitamin B3), vitamin B6, ascorbic acid (vitamin C), vitamin A, calcium, selenium, and fluoride. Okra is rich in some of the essential micronutrients, and the fact that no difference was observed in the protein efficiency ratio of its flour heated at 130oC compared with non-heated flour indicated the absence of anti-nutritional factors (Karakoltsidis and Constantinides, 1975). The okra seed meal contains more than 50% good quality protein on a fat-free, dry-weight basis, whereas most of the suitable amino acids in okra seed protein are present in amounts that are equal to or exceed the amounts in eggs, casein, and the United Nations Food and Agriculture Organization reference protein from okra source (Akingbala et al., 2003). Table 19.1 lists the amino acid composition of okra products that makes okra-based products desirable for food consumption (Savello et al., 1982) and makes okra a good source for food fortification strategies. The objective of this chapter is to appraise the level of food fortification using okra products to enrich select foods that are consumed in tropic and temperate regions of the world, including the impacts that selected processing techniques such as pretreatments may provide.

BREAD FORTIFICATION WITH OKRA FLOUR In Egypt, the nutritive value of bread produced using composite flour that contained maize was increased by supplementing it with okra flour. The resulting bread was satisfactory and comparable to wheat-based bread because okra contains sticky gluten. Although bitter taste was observed after the consumption of bread that was produced from composite flour that included fenugreek seeds as supplement, which restricted its use because of consumer acceptability constraints, there are no such restrictions for bread that includes okra flour as supplement. Young rats were used as experimental animals, and it was found that maize meal containing okra flour supplement produced the highest growth in the rats (77 g) compared to other diets with fenugreek (72 g) and cottonseed flour (48 g). The protein content in the base okra flour for the bread production was determined to be 18% (Taha, 1947). The associated benefits of okra flour in bread fortification include its slippery characteristics, which facilitate water absorption in the colon and ensure bulk in stools; the fact that is acts as a probiotic while stabilizing blood sugar; and that it binds not only

206

TABLE 19.1 Amino Acid Composition of Okra Products for Food Fortificationa Amino Acid Aspartic acid Threonine Serine Glutamic acid Proline Glycine Alanine Cystine Valine Methionine Isoleucine Leucine Tyrosine Phenylalanine Histidine Lysine Tryptophan Arginine

Whole Seeds

Full-Fat Flour

Defatted Flour

Protein Concentration

Protein Isolate

11.57 2.86 5.07 15.91 3.79 4.78 4.83 3.63 4.24 1.83 2.96 6.21 3.46 4.41 2.34 6.22 2.02 11.17

11.17 2.84 4.80 17.29 4.60 4.54 4.89 2.86 4.27 2.12 3.00 5.64 4.09 4.86 3.63 6.79 2.22 9.82

10.88 2.97 4.67 17.25 4.55 4.46 5.79 1.88 4.76 2.01 2.98 6.81 3.95 4.59 2.91 6.93 2.64 10.42

10.89 3.37 5.23 19.15 4.88 4.77 4.53 1.89 4.42 2.18 3.06 6.96 5.15 4.80 3.61 6.19 2.57 10.02

12.12 2.90 4.97 17.35 4.98 4.16 4.59 1.90 4.33 2.21 3.13 6.97 4.03 4.85 3.83 6.47 2.03 9.98

Source: Adapted from Bryant et al. (1988). a Data represent mean of duplicate determinations in grams amino acids/100 g protein.

CHAPTER 19 Potential Use of Okra Seed (Abelmoschus esculentus Moench) cholesterol but also bile acid carrying toxins dumped into it by the filtering liver (Livera, 2009). Defatted okra flour and okra full-fat flour have also been found to have in vitro protein digestibility of 81.22 and 81.94%, respectively. These values are comparable to the in vitro protein digestibility obtained for soy defatted flour and soy full-fat flour of 75.57 and 84.71%, respectively. Calculated protein efficiency ratios of okra seed products vary between 2.16 and 2.22, comparable with a range of 2.14e2.19 obtained for soy products, suggesting similarity in protein quality (Bryant et al., 1988).

CEREAL-BASED FOOD FORTIFICATION WITH OKRA FLOUR Cereal-based foods are widely utilized in many developing nations as dietary staples for adults and weaning foods for infants. In Africa, cereal-based foods account for up to 77% of total caloric consumption. The major cereal-based foods in these regions are derived mainly from maize, sorghum, millet, rice, or wheat. Although cornmeal with okra is a frequently used staple food in Cameroon (Kana Sop et al., 2008), other fermented cereal-based foods such as liquid porridge, including ogi, mahewu, and mahe, or stiff gels, including agidi, kenkey, bogobe, banku, injera, and kisra, are common and important sources of food in other developing countries (Chavan and Kadam, 1989; Osungbaro, 2009; Otunola et al., 2007). Maize is deficient in most essential nutrients, especially essential amino acids, vitamins, and minerals, but it constitutes more than 90% of the cereals consumed in many developing countries (Aminigo and Akingbala, 2004). It is reported to be low in tryptophan and lysine, which are essential amino acids needed in the diet (Akingbala et al., 2003). The inclusion of okra flour in breakfast or complementary food contributes to the dietary intake of sodium (0.03%) and potassium (2.14%). Table 19.2 lists the various okra products that can be used for food fortification and some of the associated nutritional benefits. Fiber in okra ensures bulk in stool, preventing or improving constipation better than crops with harsh seed coat such as wheat bran, which may cause some irritation and injury to the intestinal tract. The implication is that the vegetable binds excess cholesterol and toxins (in bile acids) that may cause health disorders and subsequently passes it out of the body; thus, the crop is one of the cheapest available functional food crops in the tropics and temperate regions of the world (Jenkins, 2009; Livera, 2009).

207

TABLE 19.2 Nutritional Profile of Okra Products Product

Protein (%)

Fat (%)

Fiber (%)

Ash (%)

Na (%)

K (%)

CHO (%)

20.5 34.2 21.0 35.3 30.3 24.24 4.04 41.03 39.15 54.14 69.08

14.73 25.6 d d d 16.22 1.43 29.95 29.07 1.67 0.88

36.9 8.72 29.6 21.6 9.47 23.43 43.44 1.50 2.64 4.00 0.02

5.70 5.91 5.10 5.22 6.30 4.79 3.00 6.07 5.98 8.19 5.42

0.03 0.05 d d d d d d d d d

2.14 0.81 d d d d d d d d d

d d d d d 25.44 39.69 17.12 17.68 24.03 19.16

90.13

1.08

0.05

3.09

d

d

0.00

a

Whole okra grain flour Dehulled okra grain floura Raw okra seedb Okra seed mealb Roasted okra seed mealb Okra whole seedsc Okra hullsc Okra kernelsc Okra full-fat flourc Okra defatted flourc Okra protein concentratec Okra protein isolated a

Data from Ashaye et al. (2005). Data from Aminigo and Akingbala (2004). c Data from Bryan et al. (1988). d Data from Otunola et al. (2007). b

SECTION 1 Flour and Breads

In Nigeria, maize is a staple cereal consumed in various forms, including processing such as boiled maize, roasted maize, maize flour, and ogi slurry (wet-milled maize gruels). Large amounts of nutrients such as fiber, protein, calcium, iron, phosphorous, and vitamins including thiamine, riboflavin, niacin, folic acid, and panthotenic acid are lost during the processing of cereals for ogi manufacture (Adeniji and Porter, 1978; Osungbaro, 2009). Ogi slurry is a major weaning and breakfast food in Nigeria. Attempts have been made to supplement the levels of both macro- and micronutrients in ogi with okra flour because the flour is reported to be rich in high-quality protein (Otunola et al., 2007; Oyelade et al., 2003) and to have considerable levels of most of the nutrients that are commonly lost during the manufacture of ogi (Chavan and Kadam, 1989). The proximate constitution of oil expressed from okra meal has also been found to include palmitic acid (27.2%), stearic acid (2.8%), arachidic acid (0.1%), oleic acid (43.7%), linolic acid (26.6%), and unsaponifiable matter (0.4%) (Jamieson and Baughman, 1920). Table 19.3 indicates the effect of using okra flour to supplement the nutrients lost during the processing of select cereal-based foods (maize gruel and ogi) in most developing countries. Data on the chemical composition of okra floureogi mixes indicate substantial increases in the levels of protein, increasing from 6.50% in an unsubstituted sample to 12.40% in a sample that was fortified with 50% okra flour. There were also increases in fat, crude fiber, and ash contents (Otunola et al., 2007). Also, okra seed fortification of ogi at the 20% level using defatted and roasted meals increased crude protein content by 122 and 106%, respectively. The ash contents in the mixes were also increased two- to fivefold, whereas fat increased by 1.5e2.2% (Aminigo and Akingbala, 2004). The nutritional attributes of foods that have been fortified with okra flour have been found to increase in quantity and quality (see Table 19.3). The quantity of the nutrients in the resulting food components, and hence their quality, is determined by the primary nutrients in the okra flour, the quality of which is usually affected by processing. The effect of roasting and roasting time on the antioxidant activity of okra seeds including in vitro digestibility stability under gastric and intestinal phases was determined by Adelakun et al. (2009b). The protein and fat contents of the roasted okra were affected by the roasting time. There was an initial increase in protein content of okra flour, whereas the protein slightly decreased after 20 min. The fat content and antioxidant activity decreased, whereas there was an increase in the ash and fiber content and antioxidant activity. The study showed that roasting reduced the protein value in okra flour and that its consumption in this form has the potential to prevent chronic diseases because most antioxidative activities occur in the gastrointestinal tract. Adelakun et al. (2009a) studied the influence of pretreatment on yield and chemical and antioxidant properties of a Nigerian okra seed flour, and they found that pretreatment such as soaking and blanching resulted in increases in yield and protein content. The antioxidant activity was slightly

208

TABLE 19.3 Effect of Okra Flour Fortification on Cereal-Based Staples Staple Whole maize grain flour Whole okra grain floura Dehulled okra grain floura Traditional maize gruela 10% okraemaize gruel fortificationb 40% okraemaize gruel fortificationb 0% okraeogi fortificationb 20% okraeogi fortificationb 50% okraeogi fortificationb a

Data from Ashaye et al. (2005). Data from Otunola et al. (2007).

b

Protein (%)

Fat (%)

Fiber (%)

Ash (%)

Na (mg/g)

K (mg/g)

9.3 20.5 34.2 6.7 13.6 21.9 6.50 8.20 12.40

3.99 14.73 25.6 3.33 8.72 13.08 1.66 1.80 2.34

3.31 36.9 8.72 0.90 5.98 9.04 0.27 0.29 0.34

1.70 5.70 5.91 0.31 1.64 2.6 0.05 0.08 0.11

0.08 0.03 0.05 0.03 0.04 0.05 0.01 0.03 0.06

0.35 2.14 0.81 0.18 0.24 0.37 d d d

CHAPTER 19 Potential Use of Okra Seed (Abelmoschus esculentus Moench)

TABLE 19.4 Effect of Pretreatment on Yield, Protein, Fat, Ash, Fiber, Carbohydrates, and Antioxidant Levels in Okra Flour Sample

Time (h)

Yield (%)

Protein (%)

Fat (%)

Ash (%)

Fiber (%)

Carbohydrates (%)

Antioxidant Level (% Inhibition)

Untreated S1 S2 S3 S4 S5 S6 B1 B2 B3 B4 B5

0 6 12 18 24 36 48 0.1 0.2 0.3 0.4 1.0

23.5 26.3 30.3 31.7 37.6 39.3 40.9 27.4 35.5 42.2 39.2 31.2

41.1 39.0 41.1 43.2 43.5 44.0 43.4 41.4 42.1 43.5 46.1 39.5

31.0 31.1 30.1 29.1 29.0 28.1 28.1 27.1 27.1 26.2 25.2 25.1

3.4 3.8 3.9 3.8 3.9 3.8 4.0 3.6 3.7 3.8 3.8 3.9

3.5 3.1 3.6 3.6 3.7 3.8 3.8 3.6 3.6 3.6 3.7 3.7

10.6 12.9 11.1 9.9 9.4 9.3 10.6 14.2 12.7 12.7 11.3 16.9

48.3 49.1 48.1 51.3 46.9 44.7 45.5 31.7 32.5 30.3 27.4 27.8

Source: Adapted from Adelakun et al. (2009a).

increased by soaking, whereas blanching reduced the component due to leaching. Table 19.4 presents the effect of soaking and blanching pretreatment on the yield of okra flour, protein, fat, ash, fiber, carbohydrates, and antioxidant attributes.

OKRA FLOUR AS SUPPLEMENT IN INFANT-WEANING FOODS In our study on the influence of variety on protein, fat content, and some physical characteristics of okra seeds for some cultivars of okra available in Nigeria, the seeds of the following cultivars were found to be rich in protein: LD-88, VI-104, UI4-30, 47-4, and V-35. The protein values ranged between 22 and 45% in the whole seed flour fractions of the different cultivars, whereas the fat content in the seed coat was between 4 and 10%, with 47-4 and LD-88 cultivars having the highest and least fat content, respectively (Oyelade et al., 2003). It is evident that processing involving removal of seed coat from the whole seeds before milling enhanced the protein content in all okra lines (Figures 19.1 and 19.2). This attribute probably makes the seed of the vegetable a promising alternative component in the formulation of traditional weaning foods in developing nations because it is a potential source of enhanced proteinbased foods for low-income earners. Okra seed meal as a component in weaning food increased the protein and fat contents. The preferred fractions of okra in the traditional Nigerian weaning meal have been found to be 70:30 (corneokra blends) and 90:5:5 (cornesoybeaneokra blends) (Jideani and Adetula, 1993).

Protein contents (%)

LD-88 VI-104

60

47-4 V-35

40

UI-30 20 0 Whole seed

Defatted flour

Seed coat

FIGURE 19.1 Effect of variety on the protein contents of various fractions of okra seeds. Source: Journal of Food Engineering, Vol. 57, Oyelade, O. J., Ade-Omowaye, B. I. O., and Adeomi, V. F., Influence of variety on protein, fat contents and some physical characteristics of okra seeds, pp. 111e114, Copyright Elsevier (2003).

209

SECTION 1 Flour and Breads

Fat content (%)

40 LD-88 VI-104

30

47-4 V-35

20

UI-30 10

W

ho le

se ed E nd os pe D rm ef at te d flo ur S ee d co at

0

FIGURE 19.2 Fat contents of various fractions of okra seeds as affected by variety. Source: Journal of Food Engineering, Vol. 57, Oyelade, O. J., Ade-Omowaye, B. I. O., and Adeomi, V. F., Influence of variety on protein, fat contents and some physical characteristics of okra seeds, pp. 111e114, Copyright Elsevier (2003).

TECHNOLOGICAL ISSUES

210

Okra can be used to supplement nutrient intake for the vast majority of people in the temperate and tropic regions of the world. The seed can be ground and sifted to obtain highprotein and high-oil products of considerable nutritional value. Although the literature suggests that its oil may contain considerably less gossypol, if any, the meal is an adequate substitute for wheat flour. However, potential obstacles to the use of okra seed for fortification include the constituent gossypol or gossypol-like compounds and cyclopropenoid fatty acids in the oil. The concentration of these components in okra seed and the consequent effect of cultivars on the fraction require validated and standardized protocols because cyclopropenoid has been found to be toxic to humans (Martin and Rhodes, 1983). Analysis of various components of okra indicates a significant influence on proximate constituents. Okra dehulling is a major technological operation for protein concentration or isolation in okra seeds. The protein derived from okra has been reported to be of high quality (Oyelade et al., 2003), comparable to that obtained from soy products and cottonseed flour. Efforts must be amplified if the potential of okra seed is to become a reality because dehulling has been identified as a major constraint to effective utilization of okra in food fortification programs. Therefore, the use of commercial blenders to dehull okra, which has been reported by Bryan et al. (1988), merits further investigation in order to obtain high-quality okra products. In many developing nations, including Nigeria, for mechanization of agriculture to succeed, it must be based on domestic engineering initiatives to design, develop, and manufacture locally most of the tools, equipment, and machines needed for all agricultural production field operations, postharvest processes, and other rural industrial activities (Odigboh, 1999). Investigation of the physicochemical properties of okra products could provide a suitable benchmark as an indication of the need to develop improvised processing equipment for the crop. Required equipment includes solar driers for dehydration, seed dehulling equipment, an indigenous canning line, blanching equipment, and mechanical press for oil extraction (Oyelade and Ade-Omowaye, 2009). Thus, okra, due to its enormous potential in tropic and temperate regions, including potential production of biomass from its foliage and fiber from the dried stems and matured pods, which may be used for paper pulp or in the textile industry or as fuel (Martin and Ruberte, 1981), should be an impetus to revitalize dwindling global indigenous technology and develop crop processing equipment in the geographical locations where it is grown. In addition, okra mucilage could also find useful application in jaggery production and paper sizing. Grated okra could be used as a thickener, binder, or flavoring agent (Oyelade and Ade-Omowaye, 2009).

CHAPTER 19 Potential Use of Okra Seed (Abelmoschus esculentus Moench) Some basic engineering properties of food crops relevant to the design of crop processing equipment for okra seeds have been determined for the seeds of some preferred okra cultivars in Nigeria, with an average diameter of 3.99e4.71 mm, surface area of 28.27e88.92 cm2, average masses of seeds varying between 0.05 and 0.06 g, and average density varying from 0.11 to 0.32 g/cm2 (Oyelade et al., 2003). Calisir et al. (2005) determined some physicochemical properties of okra seeds that are commonly grown in Turkey and that have varying dimensional properties to those reported for some Nigerian okra. Therefore, efforts should be amplified to determine reliable physicochemical parameters of all known okra lines in various geographical locations in order to adequately design and construct functional equipment for okra on a global scale.

CONCLUSION Okra flour has huge potential to be used to enrich foods in order to provide adequate nutrients for individuals for whom daily nutritional needs are not being met. Based on the nutrient profile of okra, including the amino profile and the effect of processing on this, human consumption of okra flour can be promoted because of its positive health effects. However, considerable effort needs to be directed at addressing associated technological issues regarding effective utilization of the food product in food fortification, including the following: l

l

l

l

The constituent gossypol or gossypol-like compounds and cyclopropenoid fatty acids in the oil The constraint of dehulling to produce high-quality okra products for effective utilization in food fortification programs Studies on the physicochemical properties of okra products to provide a suitable benchmark for the development of functional okra processing equipment Determination of the effect of variety and agronomical traits on nutritional and physicochemical parameters of all known okra lines to present okra to wider population groups as a vital food crop.

SUMMARY POINTS l l l l

l

Okra is an important crop in temperate and tropical climates. The seed of okra is high in quality amino acids. Due to its high-quality protein, it can be used in flour fortification. Okra flour has the potential to be used to enrich foods in order to provide adequate nutrients for individuals for whom daily nutritional needs are not being met. These nutrients may be affected by various processing procedures. The seeds can be a source of antioxidant, which is essential in maintaining health.

References Adelakun, O. E., Oyelade, O. J., Ade-Omowaye, B. I. O., Adeyemi, I. A., & Van de Venter, M. (2009a). Chemical composition and the antioxidative properties of Nigerian okra seed (Abelmoschus esculentus Moench) flour. Food and Chemical Toxicology, 47, 1123e1126. Adelakun, O. E., Oyelade, O. J., Ade-Omowaye, B. I. O., Adeyemi, I. A., Van de Venter, M., & Koekemoer, T. C. (2009b). Influence of pretreatment on yield, chemical and antioxidant properties of a Nigerian okra seed (Abelmoschus esculentus Moench) flour. Food and Chemical Toxicology, 47, 657e661. Adeniji, A. O., & Porter, N. N. (1978). Properties of ogi powders made from normal fortified and opaque-2 corn. Journal of Food Science, 43, 1571. Akingbala, J. O., Akinwande, B. A., & Uzo-Peters, P. I. (2003). Effects of color and flavour changes on acceptability of ogi supplemented with okra seed meals. Plant Foods for Human Nutrition, 58, 1e9. Allen, L., Benoist, B., Dary, O., & Hurrell, R. (2006). Guidelines on Food Fortification with Micronutrients. Geneva: Word Health Organization/Food and Agriculture Organization of the United Nations. Aminigo, E. R., & Akingbala, J. O. (2004). Nutritive composition of ogi fortified with okra seed meal. Journal of Applied Sciences & Environmental Management, 8(2), 23e28.

211

SECTION 1 Flour and Breads

Ashaye, O. A., Akingbala, J. O., Obatolu, V. A., & Fasoyiro, S. B. (2005). Improving processing technology and nutritional composition of Nigerian traditional breakfast gruel from corn and okra. Journal of Agricultural and Food Information, 6(1), 77e87. Bryant, L. A., Montecalvo, J., Jr., Morey, K. S., & Loy, B. (1988). Processing, functional, and nutritional properties of okra seed products. Journal of Food Science, 53(3), 810e816. Calisir, S., Ozcan, M., Haciseferogullari, H., & Yildiz, M. U. (2005). A study on some physico-chemical properties of turkey okra (Hibiscus esculenta L.) seeds. Journal of Food Engineering, 68, 73e78. Chavan, J. K., & Kadam, S. S. (1989). Nutritional improvement of cereals by fermentation. Critical Reviews in Food Science and Nutrition, 28, 349e400. Jamieson, G. S., & Baughman, W. S. (1920). Okra seed oil. Journal of the American Chemical Society, 42, 166e170. Jenkins, D. J. A. (2009). The Portfolio DietdA Combined Dietary Prescription for Cholesterol Management. Paper presented at the Alpro Foundation Symposium on Plant Nutrients and Cardiovascular Health. Nottingham, UK: University of Nottingham. November 11, 2009. Jideani, V. A., & Adetula, H. O. (1993). The potential of okra seed flour for weaning foods in West Africa. Ecology of Food & Nutrition, 29(4), 275e283. Kana Sop, M. M., Fotso, M., Gouado, I., Tetanye, E., & Amvam Zolio, P. H. (2008). Nutritional survey, staple foods composition and the uses of savoury condiments in Douala, Cameroon. African Journal of Biotechnology, 7(9), 1339e1343. Karakoltsidis, P. A., & Constantinides, S. M. (1975). Okra seed: A new protein source. Journal of Agricultural and Food Chemistry, 23, 1204e1207. Livera, J.D. (2009). Okra or Bindhi Helps Those Suffering from Diabetes and Gerd. An Open Homeo-Encyclopedia Project. Available at . Martin, F. W., & Rhodes, A. M. (1983). Seed characteristics of okra and related Abelmoscus species. Plant Foods for Human Nutrition, 33, 41. Martin, F. W., & Ruberte, R. (1981). Variability in okra seed quality. Journal of Agriculture of the University of Puerto Rico, 65, 205e211. Odigboh, E. U. (1999). Engineering Design for Strategic Supply of Appropriate Farm/Rural Machines Equipment for Enhanced Agricultural Development in Nigeria. Abuja, Nigeria: Paper presented at the National Engineering Design Conference. September 26e29, 1999.

212

Osungbaro, T. O. (2009). Physical and nutritive properties of fermented cereal foods. African Journal of Food and Science, 3(2), 23e27. Otunola, E.T., Sunny-Roberts, E.O., & Solademi, A.O. (2007). Influence of the Addition of Okra Seed Flour on the Properties of “Ogi,” a Nigerian Fermented Maize Food. Paper presented at the Conference on International Agricultural Research for Development, Tropentag 2007, University of Kassel-Witzenhausen and University of Gottingen, October 9e11, 2007. Oyelade, O. J., & Ade-Omowaye, B. I. O. (2009). Potential benefits of okra in the food and agricultural system of Nigeria. In B. S. Dankhar, & Ram Singh (Eds.), Okra Handbook: Global Production, Processing, and Crop Improvement. New York: HNB. Oyelade, O. J., Ade-Omowaye, B. I. O., & Adeomi, V. F. (2003). Influence of variety on protein, fat contents and some physical characteristics of okra seeds. Journal of Food Engineering, 57, 111e114. Savello, P. A., Martin, F. W., & Hill, J. M. (1982). Nutritional composition of okra seed meal. Journal of Agricultural and Food Chemistry, 28, 1163e1166. Taha, M. M. (1947). Value of adding cotton-seed, okra and fenugreek to maize flour. Nature, 159, 716.