International Journal of Innovative Food, Nutrition & Sustainable Agriculture 7(3):1-7 July-Sept., 2019

© SEAHI PUBLICATIONS, 2019 www.seahipaj.org ISSN: 2467-8481

Tiger nut (Cyperus esculentus): A Supper Food But Neglected By Researchers

MOHAMMED D. TOUNGOS1 & MUA’ZU BABAYOLA2.

Crop Science Department, Adamawa State University Mubi, Adamawa State, Corresponding Author Email: [email protected]; [email protected] ABSTRACT esculentus can be found wild, as a , or as a crop. Evidence exists for its cultivation in Egypt since the sixth millennium BC, and for several centuries in . In Spain, C. esculentus is cultivated for its edible tubers, called earth almonds or tiger nuts, for the preparation of de chufa, a sweet, -like beverage. However, in most other countries, it is often found in wet soils such as rice paddies and peanut farms as well as well irrigated lawns and golf courses during warm weather. The tubers were also used medicinally, taken orally, as an ointment, or as an enema, and used in fumigants to sweeten the smell of homes or clothing. The was introduced by the Arabs, first in the region. C. esculentus is also cultivated in countries such as , , , Brasil, the , , , , , , , , , , , , , , , Gambia, Guinea Bissau, , , Nigeria, , , , Northern , and , where they are used primarily as animal feed or uncooked as a side dish, but in Hispanic countries they are used mainly to make horchata, a sweet, milk-like beverage. In Northern Nigeria, it is called aya and it is usually eaten fresh. It is sometimes dried and later rehydrated and eaten. Also a snack is made by toasting the nuts and sugar coating it is popular among the Hausa children of Northern Nigeria. Also, a drink known as kunun aya is made by processing the nuts with dates and later sieved and served chilled. They have various uses, such as horchata, a nonalcoholic beverage of milky appearance derived from the tubers of the tiger nut plant mixed with sugar and water, and commonly consumed. Flour of roasted tiger nut is sometimes added to biscuits and other bakery products as well as in making oil, soap, and extracts. It is also used for the production of nougat, jam, beer, and as a flavoring agent in ice cream and in the preparation of kunnu (a local beverage in Nigeria). Kunnu is a nonalcoholic beverage prepared mainly from cereals (such as millet or sorghum) by heating and mixing with spices (dandelion, alligator pepper, ginger, licorice) and sugar. To make up for the poor nutritional value of kunnu prepared from cereals, tiger nut was found to be a good substitute for cereal grains. Tiger nut oil can be used naturally with salads or for deep frying. It is considered to be a high quality oil. Tiger nut “milk” has been tried as an alternative source of milk in fermented products, such as yogurt production, and other fermented products common in some African countries and can thus be useful replacing milk in the diet of people intolerant to to a certain extent. Because of these reasons, this product meets all the characteristics to become the best ally of citizens in their desire to find a balanced diet and promote healthy life habits. A new era for the consumption of tigernuts has begun. Until now it was strongly linked to the production of horchata but this is changing due to the production of the crop and awareness of citizens. This tuber is beginning to gain ground on its own and time will make it receive the attention it deserves from researchers, consumers and exporters. Innovation and research on the product is recommended to be continues every day in order to get best out of the crop. Keywords: Tigernut, pepper, ginger, diet and extracts.

Toungos & Babayola….. Int. J. Innovative Food, Nut. & Sust. Agric. 7(3):1-7, 2019

INTRODUCTION Tigernut (Cyperus esculentus) also called chufa sedge, nut grass, yellow nutsedge, tiger nut sedge, edible galingale, water grass or earth almond is a crop of the sedge family widespread across much of the world, Sanchez-Zapata et al (2012). It is found in most of the , including Southern Europe, and , as well as the and the , Sanchez-Zapata et al (2012) and Hart, T and Timothy H; (2013). Cyperus esculentus can be found wild, as a weed, or as a crop. Evidence exists for its cultivation in Egypt since the sixth millennium BC, and for several centuries in Southern Europe. In Spain, C. esculentus is cultivated for its edible tubers, called earth almonds or tiger nuts, for the preparation of horchata de chufa, a sweet, milk-like beverage. However, in most other countries, C. esculentus is considered a weed as stated by Hart, T and Timothy H; (2013). It is often found in wet soils such as rice paddies and peanut farms as well as well irrigated lawns and golf courses during warm weather. Zohary and Hopf estimate that C. esculentus "ranks among the oldest cultivated in ". Although noting that "chufa was no doubt an important food element in ancient Egypt during dynastic times, its cultivation in ancient times seems to have remained (totally or almost totally) an Egyptian specialty" as reported by Defelice, MS (2002). Its dry tubers have been found in tombs from predynastic times about 6000 years ago. In those times, C. esculentus tubers were consumed either boiled in beer, roasted, or as sweets made of ground tubers with honey; Macho, G.A (2014). The tubers were also used medicinally, taken orally, as an ointment, or as an enema, and used in fumigants to sweeten the smell of homes or clothing; Rene, I.J; Tracy, B.F (2006). There are almost no contemporary records of this plant in other parts of the old World. Besides Egypt, at present C. esculentus is cultivated mainly in Spain, where it is extended for common commercial purposes in mild climate areas. The plant was introduced by the Arabs, first in the Valencia region. C. esculentus is also cultivated in countries such as Guatemala, Mexico, Chile, Brasil, the United States, Lebanon, Syria, Jordan, Saudi Arabia, Oman, Iran, Iraq, Pakistan, India, Yemen, Morocco, Ivory Coast, Sudan, South Sudan, Gambia, Guinea Bissau, Ghana, Niger, Nigeria, Burkina Faso, Togo, Benin, Northern Cameroon, and Mali, where they are used primarily as animal feed or uncooked as a side dish, but in Hispanic countries they are used mainly to make horchata, a sweet, milk-like beverage. In Northern Nigeria, it is called aya and it is usually eaten fresh. It is sometimes dried and later rehydrated and eaten. Also a snack is made by toasting the nuts and sugar coating it is popular among the Hausa children of Northern Nigeria. Also, a drink known as kunun aya is made by processing the nuts with dates and later sieved and served chilled. Biology: Cyperus esculentus is an annual or , growing to 90 cm tall, with solitary stems growing from a tuber. The plant is reproduced by seeds, creeping rhizomes, and tubers, as reported by Ross, M.A; Lembi C.A, (2008). ue to its clonal nature, C. esculentus can take advantage of soil disturbances caused by anthropogenic or natural forces, Pascual-Seva, N; et al (2013) and Pascual-Seva, N; Ben et al (2013). The stems are triangular in section and bear slender 3–10 mm wide. The spikelets of the plant are distinctive, with a cluster of flat, oval seeds surrounded by four hanging, - like positioned 90 degrees from each other. They are 5 to 30 mm long and linear to narrowly elliptic with pointed tips and 8 to 35 florets. The color varies from straw-colored to gold-brown. They can produce up to 2,420 seeds per plant. The plant foliage is very tough and fibrous and is often mistaken for a grass. The roots are an extensive and complex system of fine, fibrous roots and scaly rhizomes with small, hard, spherical tubers and basal attached. The tubers are 0.3 – 1.9 cm in diameter and the colors vary between yellow, brown, and black, Raid, WS; et al (1972). One plant can produce several hundred to several thousand tubers during a single growing season. With cool temperatures, the foliage, roots, rhizomes, and basal bulbs die, but the tubers survive and re-sprout the following spring when soil temperatures remain above 6 °C (43 °F), Ross, M.A; Lembi C.A, (2008). They can re-sprout up to several years later as observed and reported by Tigernuts Traders, S.L, Tigernut oil, (2012). When the tubers germinate, many rhizomes are initiated and end in a basal near the soil surface. These basal bulbs initiate the stems and leaves above ground, and fibrous roots underground. C. esculentus is wind pollinated and requires cross as it is self–incompatible. Toungos & Babayola….. Int. J. Innovative Food, Nut. & Sust. Agric. 7(3):1-7, 2019

Agronomy: Planting is normally done on flat soils where ridges to favor the coming irrigations have previously been done. The separation between ridges is approximately 60 cm and seeds are planted manually. Distances between seeds may vary from 15 to 20 cm and seeding depth is around 8 cm. A typical seeding rate for chufa is about 120 kg of tubers/ha-1.Coscuna, Y et al (2002). They are planted between April and May and must be irrigated every week until they are harvested in November and December. Tubers develop about 6 – 8 weeks after seedling emergence and grow quickly during July and August. The maturing is around 90 – 110 days. The average yield can approach between 10 and 19 t/ha-1, Rossello-Soto, E; et al (2018) and Belewu, M.A; Abodunrin, O.A (2008). Cyperus esculentus cultivation requires a mild climate. Low temperature, shade, and light intensity can inhibit flowering as observed by Reid WS; et al (1972). Tuber initiation is inhibited by high levels of nitrogen, long photoperiods, and high levels of gibberellic acid. Flower initiation occurs under photoperiods of 12 to 14 hours per day. Soil requirements: Tubers can develop in soil depths around 30 cm (1-foot), but most occur in the top or upper part. They tolerate many adverse soil conditions including periods of drought and flooding and survive soil temperatures around −5 °C. They grow best on sandy, moist soils at a pH between 5.0 – 7.5, Reid WS; et al (1972). The densest populations of C. esculentus are often found in low-lying wetlands as reported by Abano, E.E.; Amoah, K.K. (2011). They do not tolerate salinity, Reid WS; et al (1972). Harvest and drying process: Harvest usually occurs in November or December and the leaves are scorched during the harvest. With a combine harvester, the tiger nut is pulled out of the ground. Immediately after harvesting, the tiger nuts are washed with water in order to remove sand and small stones. The drying occurs usually in the sun and can take up to three months, Zhang, He Yuan; et al (1996). The temperatures and humidity levels have to be monitored very carefully during this period. The tiger nuts have to be turned every day to ensure uniform drying. The drying process ensures a longer shelf life. This prevents rot or other bacterial infections, securing quality and high nutrition levels. Disadvantages in the drying process are shrinkage, skin wrinkles and hard nut texture as reported by Makareviciene, V.; et al (2013). Storage: Tiger nut loses a considerable amount of water during drying and storage. The starch content of the tiger nut tubers decreases and the reducing sugar (invert sugar) content increases during storage, Makareviciene, V.; et al (2013). Tiger nut can be stored dry and rehydrated by soaking without losing the crisp texture. Soaking is often done overnight. Dried tiger nuts have a hard texture and soaking is indispensable to render them edible with ease and to ensure acceptable sensory quality, Reid, W.S et al (1972). The nutritional composition/100 ml of the Spanish beverage horchata de chufas is as follows: energy content around 66 kcal, proteins around 0.5 g, over 10 g with starch at least 1.9 g, at least 2 g. Uses: Dried tiger nut has a smooth tender, sweet and nutty taste. It can be consumed raw, roasted, dried, baked or as tiger nut milk or oil. As food, dried tubers sold at the market of Yola, Mubi Hong and Gombi. Toungos, M.D;. (2019) Personal communication. The tubers are edible, with a slightly sweet, nutty flavor, compared to the more bitter-tasting tuber of the related (purple nutsedge). They are quite hard and are generally soaked in water before they can be eaten, thus making them much softer and giving them a better texture. They are a popular snack in West Africa. They have various uses, such as horchata, a nonalcoholic beverage of milky appearance derived from the tubers of the tiger nut plant mixed with sugar and water, and commonly consumed in Spain, Sanchez- zapata, E; et al (2012). Flour of roasted tiger nut is sometimes added to biscuits and other bakery products as well as in making oil, soap, and starch extracts. It is also used for the production of nougat, jam, beer, and as a flavoring agent in ice cream and in the preparation of kunnu (a local beverage in Nigeria).Personal communication (2019). Kunnu is a nonalcoholic beverage prepared mainly from cereals (such as millet or sorghum) by heating and mixing with spices (dandelion, alligator pepper, ginger, licorice) and sugar. To make up for the poor nutritional value of kunnu prepared from cereals, tiger nut was found to be a good substitute for cereal grains. Tiger nut oil can be used naturally with salads or for deep frying. It is considered to be a Toungos & Babayola….. Int. J. Innovative Food, Nut. & Sust. Agric. 7(3):1-7, 2019 high quality oil. Tiger nut “milk” has been tried as an alternative source of milk in fermented products, such as yogurt production, and other fermented products common in some African countries and can thus be useful replacing milk in the diet of people intolerant to lactose to a certain extent as stated by Hart T.C; Ives, T.H (2013). Nutrition: Despite its name, tiger nutsedge is a tuber. However, its chemical composition shares characteristics with tubers and with nuts. This tuber is rich in energy content (starch, , sugar, and protein), and dietary minerals (mainly phosphorus and potassium). The oil of the tuber was found to contain 18% saturated ( and ) and 82% unsaturated ( and ) fatty acids, Makareviciene, V; et al. (2013). Oil: Since the tubers of C. esculentus contain 20-36% oil, it has been suggested as potential oil crop for the production of . One study found that chufa produced 1.5 metric tonnes of oil per hectare based on a tuber yield of 5.67 t/ha and an oil content of 26.4%, Makareviciene, V; et al (2013). A similar 6-year study found tuber yields ranging from 4.02 to 6.75 t/ha, with an average oil content of 26.5% and an average oil yield of 1.47 t/ha, Bilall et al (2011) Fishing bait The boiled nuts are used in the UK as a bait for carp. The nuts have to be prepared in a prescribed manner to prevent harm to the fish. The nuts are soaked in water for 24 hours, and then boiled for 20 minutes or longer until fully expanded. Some anglers then leave the boiled nuts to ferment for 24–48 hours, which can enhance their effectiveness. If the nuts are not properly prepared, they can be toxic to carp. This was originally thought to have been the cause of death of Benson, a large, well-known female carp weighing 24 kg found floating dead in a fishing lake, with a bag of unprepared tiger nuts lying nearby, empty, on the bank. An examination of the fish by a taxidermist concluded tiger nut poisoning was not the cause of death, but rather the fish had died naturally, Balley, J;. (2009). Compatibility with other crops: C. esculentus is extremely difficult to remove completely once established. This is due to the plant having a stratified and layered root system, with tubers and roots being interconnected to a depth of 36 cm or more, Reid, W.S; et al (1972). The tubers are connected by fragile roots that are prone to snapping when pulled, making the root system difficult to remove intact. Intermediate rhizomes can potentially reach a length of 60 cm. The plant can quickly regenerate if a single tuber is left in place. By competing for light, water and nutrients it can reduce the vigor of neighboring plants. It can develop into a dense colony. Patch boundaries can increase by more than one meter per year. Tubers and seed disperse with agricultural activities, soil movement or by water and wind. They are often known as a contaminant in crop seeds. When plants are small they are hard to distinguish from other such as Dactylis glomerata and Elytrigia repens. Thus it is hard to discover in an early stage and therefore hard to counteract. Once it is detected, mechanical removal, hand removal, grazing, damping, and herbicides can be used to inhibit C.esculentus. As tigernuts contain these beneficial elments, it’s consumption becomes of particular interest to those who wish to maintain adequate levels of calcium and potassium. Tigernuts definitely are a super food. 4. Tigernuts provide a good amount of potassium Controlling blood pressure is one of the main functions of the potassium. And in this sense, tiger nuts, due to the high amount of this chemical helps to control the heart activity. While banana is the most known source of potassium, multiple studies have confirmed that tigernuts provide levels even higher of this electrolyte.

SEVEN (7) REASONS WHY TIGERNUTS ARE A SUPER FOOD: For all these reasons and more we want to share 7 characteristics of the tiger nuts that make them a super food and main ally in diets designed to live a healthy life. 1. High fiber content that keeps your body in shape: The chemical composition of tiger nut outlines the large amount of fiber that it contains and which is clearly beneficial to keep the digestive system in perfect shape. Ingesting fiber is the best ally to end constipation problems, since fiber is a natural stimulant to evacuate regularly. The fiber is present in all diets that aim to lose weight and are widely found in foods such as prunes, chia seeds or whole grains. However, it is proven that fiber levels found in the tiger nuts Toungos & Babayola….. Int. J. Innovative Food, Nut. & Sust. Agric. 7(3):1-7, 2019

are superior to this food. This is why these tubers are now beginning to get more and more popular. The increasing consumption of tigernut flour may seem novel, but it has been made since ancient times. Now that there is a great demand for new products and healthy flavors, when the popularity of the tiger nut begins to spread around the world. Among the benefits of consuming fiber is also the property of whet appetite. Not surprisingly, the effects observed are directly proportional: the sooner the feeling of satiety appears, better results are obtained in weight loss goals (for those involved in diets to reduce their weight). It is proven that the fiber remains longer in the body of people and provides a high caloric level. This element is also an important regulator of blood glucose levels. 2. Tiger nut milk is a substitute for cow milk: Ideal and healthy. The tiger nut, apart from flour (as noted in the previous section) is also presented in the form of milk. Apart from the traditional cow or sheep milk (the most consumed; especially the first), in recent years plant are increasing their popularity in comparison to traditional milk. For example soy milk is getting more and more adepts committed to a healthy and balanced diet. The success has been so great that, at present, soy milk is present in supermarkets and has positioned itself as a high quality product to combat, for example, high cholesterol levels. Currently, tiger nut are undergoing the same process as the soy milk. The tiger nut milk is seen as the best substitute for cow or sheep milk, because of its non - animal origin and 100% healthy fats. Rich in vitamin E and C, tiger nut combat hypertension and cholesterol. In addition, being an easily digestible food, it’s completely suitable for lactose intolerant and prevents cardiovascular problems. In essence, no doubt that, over the next few years, tiger nut milk will be claimed as a great substitute for cow milk. Its chemical composition makes it even healthier. 3. The tiger nuts are a source of magnesium: Magnesium is responsible for over 300 biochemical interactions in the body. Hence the importance of keeping the body with a beneficial dose of this essential element. The control of magnesium levels provides great advantages and 100 grams of tigernuts contribute between 13 and 17% of the daily need of a healthy adult. To adhere the calcium to the bones and thus fight osteoporosis and tooth decay, tiger nuts provide part of the needed magnesium. A good way to be full of energy is to provide the body a daily dose of magnesium. Magnesium is ideal, along with proteins, to develop the muscles. Of course, magnesium is strongly related to kidney care and prevention of menstrual problems (in women) and maintaining the body pH stable to avoid the appearance of dermatitis or fungal infections. As tigernuts contain these beneficial elments, it’s consumption becomes of particular interest to those who wish to maintain adequate levels of calcium and potassium. Tigernuts definitely are a super food. 4. Tigernuts provide a good amount of potassium: Controlling blood pressure is one of the main functions of the potassium. In this sense, tiger nuts, due to the high amount of this chemical helps to control the heart activity. While banana is the most known source of potassium, multiple studies have confirmed that tigernuts provide levels even higher of this electrolyte. To be exact, 25 tigernuts provide the amount of 139 milligrammes of potassium and proportionately outweigh the mentioned fruit. The intake of potassium - rich foods is commonly related to the proper functioning of the cells of the human body and health of vital organs. Potassium, as one of the essential minerals, regulates the amount of acid-base and helps to distribute water throughout the body. Potassium helps the body to process carbohydrates. The lack of potassium in the body causes a different amount of dysfunctions such as arrhythmia, muscle weakness, fatigue, low blood pressure or constipation. Therefore, nourish the body with this mineral becomes an essential activity, to meet the objectives that every healthy balanced diet should pursue. Toungos & Babayola….. Int. J. Innovative Food, Nut. & Sust. Agric. 7(3):1-7, 2019

5. An inexhaustible source of vegetable protein: Tigernuts, as noted, have a high nutritional value. However, when analyzing the origin of their non animal proteins, tigernuts become a round food. The latent benefit of plant proteins is the lower incidence of fat and cholesterol. Consumed regularly, tiger nuts are the ideal and perfect antioxidant for cleansing diets and elimination of toxins (based mainly on fruits and green leafy vegetables) that could serve to deprive from animal foods for a few days or forever. The vegetable protein is aligned with all the benefits described above, as for example, the natural regulation of the cardiovascular system and proper functioning of cellular activity that prevents the risk of cancer. Finally, it should be noted that the rich amino acids contained in the tigernuts are higher than the standards of the World Health Organization for other foods. 6. Dietary fiber in tiger nuts can help control diabetes: In line with the first benefit, the great contribution of healthy and balanced fiber provided by tigernuts does not raise blood glucose levels and, therefore, these foods are excellent for preventing and combating diabetes. Actually worldwide millions suffer from diabetes type 2 whose risks can trigger fatal health consequences. Therefore, maintaining the levels of blood sugar in a controlled manner is clearly a goal to pursue, but for that, you have also to remedy obesity, physical inactivity, alcohol intake, smoking or high blood pressure, primarily responsible for triggering diabetes. In this sense, tigernuts can play an important role in a healthy lifestyle, because of their high nutritional value and all the benefits described. In addition, it’s high doses of sucrose and the contained fiber have made tigernuts great substitutes for carbohydrates that do raise the level of blood sugar. 7. Tiger nut oil properties compete with olive oil: Indeed, tiger nut oil has nothing to envy the traditional oil. It’s oil is full of healthy power. Because of its high levels of oleic acid (monounsaturated), this liquid is perfect to nourish the skin and prepare it against external aggressions. In addition, tiger nut oil contains sufficient polyunsaturated fatty acids to fully meet the daily needs of the human body. Among the therapeutic properties of tiger nut oil, is, for example, the cure of eczemas or skin lesions caused by dermatophytes, as well as stimulation of calcium absorption, bone tissue regeneration or atherosclerosis, among other diseases. Beyond the therapeutic properties offered by the tiger nut oil as a food, advanced cosmetics companies begin to use it to innovate with highly tolerant products for different skin types and thanks to their high doses of vitamin E, which prevent aging.

CONCLUSION The tigernut, a super food. Because of these reasons, this product meets all the characteristics to become the best ally of citizens in their desire to find a balanced diet and promote healthy life habits. A new era for the consumption of tigernuts has begun. Until now it was strongly linked to the production of horchata but this is changing due to the production of the crop and awareness of citizens. This tuber is beginning to gain ground on its own and time will make it receive the attention it deserves from researchers and consumers and exporters. Innovation and research on the product is recommended to be continues every day in order to get best out of the crop.

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