Tigernut Processing: Its Food uses and Health Benefits
The search for lesser known and underutilized crops, many
of which are potentially valuable as human and animal foods has been intensified
to maintain a balance between population growth and agricultural productivity,
particularly in the tropical and sub-tropical areas of the world. Tigernut (Cyperus
esculentus) is an underutilized crop of the family Cyperaceae which produces
rhizomes from the base and tubers that are somewhat spherical. Many authors
have reported the nutritional value of tigernut. Tigernut produces high quality
oil about 25.5% of its content and protein about 8% of the nut. The nut is high
in oil content and the oil was implicated as lauric acid grade oil, non acidic
stable and very low unsaturated. The nuts were valued for their nutritious starch
content, dietary fibre and carbohydrate. The nut is also very rich in mineral
content (Sodium, Calcium, Potassium, Magnessium, Zinc and traces of Copper.
Its tubers are also said to be aphrodisiac, carminative, diuretic, emmanogogue,
stimulant and tonic. Tigernut has also been reported to be used in the treatment
of flatulence, indigestion, diarrhoea, dysentery and excessive thirst. In addition,
tigernut has been demonstrated to contain higher essential amino acids than
those proposed in the protein standard for satisfying adult needs. There is
the need for increased utilization and awareness about its health benefits.
Received: April 15, 2010;
Accepted: June 02, 2010;
Published: July 05, 2010
Tigernut (Cyperus esculentus L.) is an underutilized crop which belongs
to the division-Magnoliophyta, classliliopsida, order - cyperales and family-Cyperaceae
(family) and was found to be a cosmopolitan perennial crop of the same genus
as the papyrus plant. Other names of the plant are earth almond as well as yellow
nut grass (Odoemelan, 2003; Belewu
and Belewu, 2007). Tigernut has been cultivated since early times (chiefly
in south Europe and West Africa) for its small tuberous rhizomes which are eaten
raw or roasted, used as hog feed or pressed for its juice to make a beverage.
Non-drying oil (usually called chufa) is equally obtained from the rhizome.
In West Africa, the plant is gathered from the wild while it is a troublesome
weed in planted field in S. United States (Belewu and Belewu,
2007). The nut was found to be rich in myristic acid, oleic acid, linoleic
acid (Eteshola and Oraedu, 1996). In Egypt, it is used
as a source of food, medicine and perfumes (De-Vries, 1991).
Tigernut is commonly known as earth almond, chufa and chew-fa and Zulu nuts.
It is known in Nigeria as Aya in Hausa, Ofio in Yoruba and Akiausa in Igbo where
three varieties (black, brown and yellow) are cultivated. Among these, only
two varieties, yellow and brown are readily available in the market. The yellow
variety is preferred to all other varieties because of its inherent properties
like its bigger size, attractive colour and fleshier body. The yellow variety
also yields more milk upon extraction, contains lower fat and more protein and
possesses less anti-nutritional factors especially polyphenols (Okafor
et al., 2003). Tigernut can be eaten raw, roasted, dried, baked or
be made into a refreshing beverage called Horchata De Chufas or tigernut milk
(Fig. 1).Tigernut milk is a very nutritive and energetic drink,
both for young and old. It is a tremendously high in starch, glucose and proteins.
Also rich in minerals like Potassium, Phosphorous, Vitamins E and C. Tigernut
milk contains a large amount of Oleic acid and is cardiac preventive. It defends
the internal mechanisms and prevents both constipation and diarrhoea. Tigernut
milk has never been found to produce allergy (TIGERNUTS TRADERS, Belewu
and Abodunrin, 2008). It also finds uses as a flavouring agent for ice cream
and biscuits (Cantalejo, 1997), as well as in making
oil, soap, starch and flour. Although, many researchers have worked on tiger
nut (Eteshola and Oraedu, 1996; De-Vries,
1991; Cortes et al., 2005; Addy
and Eteshola, 1984), yet there is the need for increased utilization and
awareness about its health benefits. Belewu and Abodunrin
(2008) has also found its usefulness in the preparation of kunun (a local
beverage in Nigeria). The chemical composition and functional properties of
flour produced from two varieties (yellow and brown) of tigernut (Cyperus
esculentus) have been studied (Oladele and Aina, 2007)
which could find useful application in food formulation (Table
1, 2). The inclusion of 33.33% of Tigernut in the diet
of cockerel starters was reported by Bamgbose et al.
(2003). It has also been reported that, tigernut, with its inherent nutritional
and therapeutic advantage, could serve as good alternative to cassava in baking
industry (Ade-Omowaye et al., 2008).
|| Flowchart showing tigernut flour processing
Fermentation process has also been applied to improve the nutrient of the tigernut
flour (Adejuyitan et al., 2009).
HEALTH BENEFITS FROM TIGERNUT CONSUMPTION
Tigernut (Cyperus esculentus), an underutilized crop, was reported to
be high in dietary fibre content, which could be effective in the treatment
and prevention of many diseases including colon cancer, coronary hearth diseases,
obesity, diabetics and gastro intestinal disorders (Anderson
et al., 1994). Tigernut flour has been demonstrated to be a rich
source of quality oil and contains moderate amount of protein. It is also an
excellent source of some useful minerals such as iron and calcium which are
essential for body growth and development (Oladele and Aina,
2007). The process of flour production is as shown in Fig.
2. Its tubers are also said to be aphrodisiac, carminative, diuretic, emmanogogue,
stimulant and tonic (Chopra et al., 1986; Chevallier,
1996). Tigernut has also been reported to be used in the treatment of flatulence,
indigestion, diarrhoea, dysentery and excessive thirst (Chevallier,
1996). In addition, tigernut has been demonstrated to contain higher essential
amino acids than those proposed in the protein standard by the FAO/WHO
(1985) for satisfying adult needs (Bosch et al.,
2005). Tigernut milk has been found to be good for the Arteriosclerosis
which contains Arginina which is a precursor of nitric oxide which helps to
the vein expanded effect. Tigernut milk without sugar can be drunk for diabetics
for its content in Carbohydrates which a base of sucrose and starch (without
glucose) and due to its content of Arginina which liberates the hormone that
produces the insulin. Tigernut milk is also an ideal drink for people who are
not able to take gluten and also for those who are able to take cows milk
and derivatives. It could also be recommended for those who have heavy digestions,
flatulence and diarrhea because it provides us a lot of digestive enzymes like
catalase, lipase and amylase (TIGERNUTS TRADERS).
Considering the nutritive and health benefits of the underutilized tigernuts, there is the need for increased utilization and awareness of its health benefits. Moreover it is suggested that products from Tigernuts should be encouraged so as to solve the problem of protein-calorie malnutrition in Africa more so that high price of imported milk and milk products (for instance) coupled with poor milk production in Nigeria in particular and Africa in general seem to have made consumers more ready to accept milk produced from plant sources.
Addy, E.O. and E. Eteshola, 1984.
Nutritive value of a mixture of tigernut tubers (Cyperus esculentus
L.) and baobab seeds (Adansonia digitata
L.). J. Sci. Food Agric., 35: 437-440.CrossRef | Direct Link |
Adejuyitan, J.A., E.T. Otunola, E.A. Akande, I.F. Bolarinwa and F.M. Oladokun, 2009.
Some physicochemical properties of flour obtained from fermentation of tigernut (Cyperus esculentus
) sourced from a market in Ogbomoso, Nigeria. Afr. J. Food Sci., 3: 51-55.Direct Link |
Ade-Omowaye, B.I.O., B.A. Akinwande, I.F. Bolarinwa and A.O. Adebiyi, 2008.
Evaluation of tigernut (Cyperus esculentus
)-wheat composite flour and bread. Afr. J. Food Sci., 2: 87-91.Direct Link |
Anderson, J.W., B.M. Smith and N.J. Gustafson, 1994.
Health benefits and practical aspects of high fibre diets. Am. J. Clin. Nutr., 59: 1242S-1247S.Direct Link |
Bamgbose, A.M., D. Eruvbetine and W. Dada, 2003.
Utilization of tigernut (Cyperus rotundus
L.) in the diets for cockerel starters. Bioresour. Technol., 89: 245-248.CrossRef |
Belewu, M.A. and K.Y. Belewu, 2007.
Comparative physico-chemical evaluation of tiger-nut, soybean and coconut milk sources. Int. J. Agric. Biol., 9: 785-787.Direct Link |
Belewu, M.A. and O.A. Abodunrin, 2008.
Preparation of kunnu from unexploited rich food source: Tiger nut (Cyperus esculentus
). Pak. J. Nutr., 7: 109-111.CrossRef | Direct Link |
Bosch, L., A. Alegria and R. Farre, 2005.
RP-HPLC determination of tigernut and orgeat amino acid contents. Food Sci. Technol. Int., 11: 33-40.Direct Link |
Cantalejo, M.J., 1997.
Analysis of volatile components derived from raw and roasted earth almond (Cyperus esculentus
L.). J. Agric. Food Chem. 45: 1853-1860.
Cortes, C., M.J. Esteve, A. Frigola and F. Torregrosa, 2005.
Quality characteristics of horchata (A Spanish vegetable beverage) treated with pulsed electric fields during shelf-life. Food Chem., 91: 319-325.CrossRef |
Chevallier, A., 1996.
The Encyclopedia of Medicinal Plants. Dorling Kindersley Publishers, London, UK
Chopra, R.N., S.L. Nayar and I.C. Chopra, 1986.
Glossary of Indian Medicinal Plants. Council of Science Industrial Research, New Delhi, India, Pages: 262
De Vries, F.T., 1991.
Chufa (Cyperus esculentus
, Cyperaceae): A weedy cultivar or cultivated weed?. Econ. Bot., 45: 27-37.Direct Link |
Eteshola, E. and A.C.I. Oraedu, 1996.
Fatty acid compositions of tigernut tubers (Cyperus esculentus
L.), baobab seeds (Adansonia digitata
L.) and their mixture. J. Am. Oil Chem. Soc., 73: 255-257.CrossRef | Direct Link |
Expert Consultation. Energy and Protein Requirements. World Health Organization, Geneva
Odoemelan, S.A., 2003.
Chemical composition and functional properties of conophor nut flour (Tetracarpidium conophorum
) flour. Int. J. Food Sci. Technol., 38: 729-734.CrossRef | Direct Link |
Okafor, J.N.C., J.I. Mordi, A.U. Ozumba, H.M. Solomon and O. Olatunji, 2003.
Preliminary studies on the characterization of contaminants in tigernut (Yellow variety). Proceedings of the 27th Annual Nigerian Institute of Food Science and Technology Conference, October 13-17, 2003, Kano, Nigeria, pp: 210-211
Oladele, A.K. and J.O. Aina, 2007.
Chemical composition and functional properties of flour produced from two varieties of tiger nut (Cyperus esculentus
). Afr. J. Biotechnol., 6: 2473-2476.CrossRef | Direct Link |