**5. Nutritive properties and health benefits of some selected underutilised grains and seeds**

#### **5.1 African yam bean** *(Sphenostylis stenocarpa)*

African yam bean (*Sphenostylis stenocarpa)* is one of the under-utilised hardy, cheap, protein-rich legume indigenous to Africa with great medicinal values [63]. The plant, when harvested, can be consumed as seed and tuber [64]. African yam bean seed contains protein with a value range between 19 and 30%. The seed is also rich in dietary fibre, carbohydrate, and essential minerals such as calcium, iron, zinc, and magnesium, with values as high as those of other vital legumes [65]. The carbohydrate composition of African yam bean is majorly starch with slowly digestible properties beneficial for diabetic patients [66]. African yam bean is also a good source of non-starchy polysaccharides, reducing the risks posed by cardiovascular disorder, coronary heart diseases, cancers, type 2 diabetes, and other lifestyle disorders [67]. African yam bean seed has a low-fat content when compared with crude legumes such as soybean and groundnut. The low-fat content of African yam bean seed makes it ideal as a promising food crop for weight management [66]. The prevalent amino acids in African yam bean include aspartic acid, glutamic acid, leucine and lysine. The fortification of protein-deficient cereal-based diets with African yam bean addresses kwashiorkor and marasmus among infants [68]. It is a hearty food in west Africa, where millions are suffering from protein-energy malnutrition. African yam bean is used to fortify and enrich foods low in protein to address the problem of protein malnutrition [64]. African yam bean is used as composite flour with rice and brown cowpea seeds, breakfast meals, maize-African yam bean meal composite, African yam bean enriched fufu, traditional snack food, and as imitation yoghurt [64, 69].

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body [83].

fibre content.

*Nutritional Composition of Grain and Seed Proteins DOI: http://dx.doi.org/10.5772/intechopen.97878*

**5.2 Bambara groundnut (***Vigna subterranean)*

bowel syndrome, and inflammatory bowel disease [75].

**5.4 Winged bean (***Psophocarpus tetragonolobus***)**

**5.3 Pigeon pea (***Cajanus cajan)*

Bambara groundnut (*Vigna subterranean*) is the third most important in most parts of Africa legume after peanuts and cowpeas. Bambara seeds (ripe or immature) are nutrient-rich and unusually high in amino acid, with more methionine than other grain legumes. They contain approximately 64.4% carbohydrate, 23.6% protein, 6.5% oil, 5.5% fiber, and are rich in micronutrient [70, 71]. Bambara groundnut is a good source of magnesium, calcium, iron, zinc, and potassium [32]. Bambara seeds and flour are used to produce myriads of traditional foods in Africa [72]. It can be used as a condiment in cooking, making flour or eaten as a snack. Bambara groundnut can be pounded into flour and used to make a stiff porridge. Raw and cooked seeds of Bambara groundnut have an abundance of epicatechin and catechin flavonoids [73]. Catechin and epicatechin polymerize to form proanthocyanidins, also known as condensed tannins. Proanthocyanidins are documented with nutraceutical properties such as cardioprotective, antitumor, antioxidant, and neuroprotective properties [74]. The nutritional profile of Bambara groundnut sustains the growth of probiotics (live microorganisms which confer certain health benefits on their hosts). These benefits are therapeutic, suppressing the growth and activity in conditions like infectious diarrhoea, irritable

Pigeon pea (*Cajanus cajan*) is mainly cultivated as edible seed grain and an alternative source of protein among farmers in lean times [76]. Pigeon pea is a good source of protein, dietary fibre, and various vitamins: thiamin, magnesium, phosphorus, potassium, copper, and manganese. Pigeon pea is also low in saturated fat, cholesterol, and sodium. Pigeon pea is a good source of protein, dietary fibre, and various vitamins: thiamin, magnesium, phosphorus, potassium, copper, and manganese. The potassium found in pigeon pea is best described as a vasodilator; it helps reduce the constriction of blood vessels, thereby lowering the risk of hypertension and other cardiovascular diseases [77]. Pigeon pea has a densely packed protein content responsible for routine healing and regeneration of cells in the human body. Pigeon pea has high folate levels, which helps prevent anaemia and nueral tube defects in unborn babies [78]. Pastes from mashed pigeon pea is used in traditional medicine for the treatment of haemorrhoids [79]. Pigeon pea is low in saturated fat and cholesterol and moderate in terms of dietary

Winged bean (*Psophocarpus tetragonolobus*) is an underutilised, nutrient-rich legume with potential as a significant multi-use food crop. Winged bean seed contains high dietary protein due to its amino-acid content, substantial protein bioavailability, and low antinutritional factors [80]. The carbohydrate content in unprocessed winged bean seed is higher than in processed winged bean seed [81]. The moderate carbohydrate content in winged bean flour makes it a good source of energy in breakfast formulations. The crude fibre content of winged bean seed is reported higher than that of most legumes. The seeds can be functional food with health benefits associated with soluble and insoluble fibre [82]. Winged bean seed can be dried and ground into flour and brewed to make a coffee-like drink. Winged bean is rich in protein and tocopherol, facilitating the utilisation of vitamin A in the *Grain and Seed Proteins Functionality*

Oats a vital cereal crop with high dietary fibre content and nutritive value [56]. Oat consumption is beneficial to man because it possesses quality protein with the right amino-acid balance, minerals, vitamins, dietary fibres, including functional protein, lipid, starch components ß-glucan and phytochemicals [57]. Oats are high in antioxidants, including avenanthramides. These compounds help reduce blood pressure and have anti-inflammatory and anti-itching effects [58]. The health benefits associated with the nutritional fibres have increased interest in its use as a food ingredient in various food products by the food industry [59, 60]. Food products derived from oat include oatmeal, porridge, granola bars, bread, biscuits, cookies, oat-based probiotic drink, oat-based breakfast cereals, flakes and infant food.

Grain amaranth is not a true grain but contains all nine essential amino acids missing from most grains. Amaranth is a good source of bioactive peptides [61]. Niacin, riboflavin and thiamine are essential micronutrients present in grain amaranth. These micronutrients enhance proper blood circulation, healthy functioning of the nervous system, maintenance of the gastrointestinal tract and proper metabolism of proteins and carbohydrate [62]. Grain amaranth is rich in protein, carbohydrate, fat, ash and energy needed for healthy living. It also contains essential minerals, namely zinc, iron, magnesium and manganese. These minerals stabilise the immune, alleviate anaemic conditions, and enhances the infant's growth [62]. Grain amaranth is popular in gluten-free baking as muffins and puffed granola.

**5. Nutritive properties and health benefits of some selected** 

African yam bean (*Sphenostylis stenocarpa)* is one of the under-utilised hardy, cheap, protein-rich legume indigenous to Africa with great medicinal values [63]. The plant, when harvested, can be consumed as seed and tuber [64]. African yam bean seed contains protein with a value range between 19 and 30%. The seed is also rich in dietary fibre, carbohydrate, and essential minerals such as calcium, iron, zinc, and magnesium, with values as high as those of other vital legumes [65]. The carbohydrate composition of African yam bean is majorly starch with slowly digestible properties beneficial for diabetic patients [66]. African yam bean is also a good source of non-starchy polysaccharides, reducing the risks posed by cardiovascular disorder, coronary heart diseases, cancers, type 2 diabetes, and other lifestyle disorders [67]. African yam bean seed has a low-fat content when compared with crude legumes such as soybean and groundnut. The low-fat content of African yam bean seed makes it ideal as a promising food crop for weight management [66]. The prevalent amino acids in African yam bean include aspartic acid, glutamic acid, leucine and lysine. The fortification of protein-deficient cereal-based diets with African yam bean addresses kwashiorkor and marasmus among infants [68]. It is a hearty food in west Africa, where millions are suffering from protein-energy malnutrition. African yam bean is used to fortify and enrich foods low in protein to address the problem of protein malnutrition [64]. African yam bean is used as composite flour with rice and brown cowpea seeds, breakfast meals, maize-African yam bean meal composite, African yam bean enriched fufu, traditional snack food, and as imitation yoghurt [64, 69].

**underutilised grains and seeds**

**5.1 African yam bean** *(Sphenostylis stenocarpa)*

**4.7 Oats**

**4.8 Grain amaranth**

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