Makhana (Euryale ferox salib) (मखाना) is considered as a potential aquatic cash crop in India especially in Bihar. Commercially, it is grown in Mithilanchal districts of Bihar (Madhubani and Darbhanga). It is adapted to the tropical climate of India and found in natural, wild forms in various parts of north-east India (Assam, Meghalaya, and Odisha) and scattered pockets of central and northern India (e.g. Gorakhpur and Alwar). However, it occurs in wild form in Japan, Korea, Bangladesh, China and Russia (Shanker et al. 2010).
Makhana belongs to Nymphaeaceae family which has floating leaf and emergent macrophyte. The leaves are orbicular, floating and glabrous, green and corrugated above and deep purple beneath, supported by stout, porous and prickly ribs. The popped expanded kernel of the gorgon nut (Euryale ferox) which is a monotypic genus, is characterized by its hard seed coat (shell), black colour and round shape seed.
Makhana cultivation requires minimum expenditure as new plants germinate from the seeds left over from the last harvest. The only investment required is in thinning out the overgrowths, transplanting into sparse areas, adding insecticides and the collection of dispersed seeds from the pond bed during harvesting. The cultivation of this aquatic crop involves clearing of pond, broadcasting of seeds, thinning and gap filling, plant protection, harvesting and collection of seed. Ponds under running cultivation do not require broadcasting as saplings are produced from the left over seeds.
The entire floor of the pond is swept by experienced fishermen to form heaps of the sunken seeds that are scooped out with the help of a horn shaped split bamboo contrivance. Smaller and lighter seeds which float on the water are collected with the help of small nets. Collected seeds are thoroughly thrashed by feet to remove the membranous cover. The average yield of seeds varies from 2.5-3.0 tonnes per hectare of pond.
Processing of makhana seeds are very tedious and still carried out by traditional methods due to lack of new processing technology. Seeds are sun-dried in the morning, so that the moisture content reaches around 31 %. Water is spread out to keep the seeds fresh and to maintain the moisture content optimum. The other steps of processing involves drying, grading, pre-heating and tempering, roasting and popping. After processing makhana seeds are dried to facilitate removal of kernel from the seed coat, and passed through different size of sieves to differentiate them into 2-3 grades. Uniform heat transfer occurs when seeds of same size are heated during preheating and roasting. Graded seeds are heated in cast iron pan with continuous stirring over fire at 230° C -335° C for approximately 6 minutes. When a crackling sound is heard, 5-7 seeds are taken out, kept on a hard surface and hitted with a wooden hammer. Seed coat breaks and due to sudden release of pressure, the kernel pops out in expanded form and seed coats are then removed manually. The edible part of makhana seed is perisperm and the popped kernels known as makhana, are polished by rubbing it against baskets made of bamboo splits without any delay to avoid absorption of moisture.
Makhana (Euryale ferox Salisb.) is one of the most common dry fruits due to low fat content, high contents of carbohydrates, protein and minerals. The calorific value of raw seeds (362 k cal/100g) and puffed seeds (328 k cal/100g) lie close to staple foods like wheat, rice, other cereals and some aquatic plants like Nelumbo and Trapa (Jha et al. 1990). The chemical constituents of the popped kernels (g/100g) are 12.8g moisture, 76.9g carbohydrate, 9.7g proteins, 0.1g fat, 0.5g total minerals, 0.02g calcium, 0.9g phosphorus and 0.0014g iron (Nath et al. 1985) which makes it comparable to dry fruits such as almond, walnut, cashew nut and coconut . Both raw and popped makhana are fairly rich in sixteen type’s essential amino acids (Bilgrami et al. 1983). The values relating to essential amino acid index (EAAI) and chemical score (CS) of makhana are close to that of fish (Jha et al. 1991).The EAAI in raw Makhana and popped Makhana are 93 % and 89 % which were higher than the values for rice (83%), wheat (65 %), bengal gram (81.5%), cow’s milk (88.8 %), fish (89.2 %), and mutton (87.24 %) (Eggum, et al. 1979; Sikka et al. 1979; Jha 1987).
Makhana finda a lot of medicinal uses in the Indian and Chinese system of medicine. Makhana is recommended for treatment of diseases regarding respiratory, circulatory, digestive, excretory and reproductive systems (Qudrat et al. 2000).The edible seed is known for its tonic, astringent, deobstruent, anti-rheumatic, anti-diuretic and roborant properties. It is also utilized to overcome postnatal weaknesses in women and in case of men its aphrodisiac and spermatogenic potential is utilized (Jha et al. 1991). Ayurveda, the Indian system of medicine recommends makhana to be beneficial in Tridosas (the seminal Ayurvedic theory of diagnosing diseases on the basis of three principal defects of the body), especially in Vata (rheumatic disorders) and Pitta (bile disorders).In Unani system of medicine makhana is used against dysmenorrhoea. According to the principles of Chinese medicine, its main functions is to notify the spleen and stop diaorrhea, to strengthen the kidneys and control the essence and to dispel dampness (Hsu et al. 1951). Makhana is used as a tonic and for the treatment of leucorrhoea and good immunostimulant (Puri et al. 2000).
In spite of the unique properties of makhana, the consumers have lack of information about the product and its various uses and hence it has not been able to make enough strides into the consumers mind space. The benefits of the wonder crop have not been disseminated properly and the sector needs urgent attention.
Bilgrami, K.S.; Sinha, K.K.; Singh, A., (1983). Chemical changes in dry fruits during aflatoxin elaboration by Aspergillus flavus L. Current Science, 52 (20): 960-64.
Boyd, C.E., (1968). Fresh water plants: a potential source of protein. Economic Botany, 23: 123-27.
Eggum B.O.; Duggal, S.K., (1977). The protein quality of some Indian dishes prepared from wheat. Journal of science food and Agriculture, 28:1052-56
Hsu, H.; Cho, C., (1951) The nutritive value of Chinese formula “su-shin”. Journal of Taiwan Pharm. Association., 3: 25-28.
Jha, V., (1987). Cytochemoecological studies of Euryale ferox Salisb, in north Bihar. Ph.d. Thesis, Ranchi University, Ranchi, India. 1987.
Jha, V.; Barat, G.K.; Jha, U.N., (1991) A Nutritional evaluation of Euryale ferox Salisb (Makhana). Journal of food science and Technology. 8 (5):326-28
Jha, V.; Kargupta, A.N.; Dutta, R.N.; Jha, U.N.; Mishra, R.K.; Saraswati ,K.C., (1991). Ultilization and Conservation of Euryale ferox Salisbury in Mithila (North Bihar) India. Aquatic Botany, 39: 259-314.
Nath, B.K.; Chakraborty, A.K., (1985). Studies on the Amino acid composition of Euryale ferox salisb. Journal of food science and Technology, 22: 293.
Puri, A.; Sahai, R.; Singh, K.L., (2000). Immunostimulant activity of dry fruits and plants materials used in Indian traditional medical system for mothers after child birth and invalids. Journal Ethnopharmacology, 71 (1-2):89-92.
Qudrat, I.; Khuda, M.; Mukherji, B.D.; Hossain, M.A.; Khan, N.A., (2000). Properties of certain starch varieties and their sources in East Pakistan. Pakistan Journal of Scientific and Industrial Research, 159-162.
Shankar,M. ; Chaudhary,N.; Singh,D., (2010). A Review on Gorgon Nut, International Journal of Pharmaceutical & Biological Archives, 1(2):101 – 107
Sikka, K.C.; Singh, R.; Gupta, D.P.; Duggal, S.K., (1979). Comparative nutritive value of fish protein concentrate from different species of fishes. Journal of Agriculture and Food Chemistry. 27: 946-49.
Vikash Kumar and Anjani Kumar
Indian Institute of Technology, Kharagpur- India