Cocoyam (corms and cormels)—An underexploited food and feed resource


Cocoyams (old-taro: Colocasia esculenta; newtannia: Xanthosoma sagittifolium) yield corms as root crops produced in regions of tropical and subtropical developing countries. In certain countries such as Ghana, there are surpluses in production but deficits in cereals. Cocoyams are used in a range of indigenous foods. Post harvest losses are high due to mechanical damage of corms during harvest and microbial attacks on such damaged corms during storage. Cocoyams contain, on average, 25% starch (wet weight basis) with A-type structures characterized by small granule size (<1.5 μm). Non-starch polysaccharides in cocoyams confer gummy properties to the starch. However, mechanical effects of raphides—crystals of calcium oxalate and other components—produce irritation when raw corm tissue is ingested resulting in several levels of discomfort. With appropriate processing, cocoyams could be a rich source of starch for food and industrial applications and corms have potential for new product development. Stabilizing cocoyam crops and adding value could greatly improve its utilization in cocoyam producing countries.

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P. Owusu-Darko, A. Paterson and E. Omenyo, "Cocoyam (corms and cormels)—An underexploited food and feed resource," Journal of Agricultural Chemistry and Environment, Vol. 3 No. 1, 2014, pp. 22-29. doi: 10.4236/jacen.2014.31004.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] FAO (2000) Production yearbook. FAO, Rome.
[2] FAO (1988) Production yearbook. FAO, Rome.
[3] FAO (1991)) Production yearbook. FAO, Rome.
[4] MoFA (2010). Agriculture in Ghana facts and figures. Ministry of Food and Agriculture, Accra.
[5] O’Hair, S.K. (1984) Farinaceous crops. In: Martin, F.W., Ed., Handbook of Tropical Crops, CRC, Boca Raton, 109-138.
[6] Purseglove, J.W. (1979) Tropical Crops: Monocotyledons, 4th Edition, Longmann, London, 58-74.
[7] Rubatzky, V.E. and Yamagushi, M. (1997) Edible aroids. In: Rubatzky, V.E. and Yamagushi, M., Eds., World Vegetables. Principles, Production and Nutritive Value, 2nd Edition, Chapman & Hall: International Thomson Publishing, New York, 183-196.
[8] Opara, L.U. (2000) Edible ar-oids—Post operation. FAO, Rome.
[9] Passam, H.C. (1982) Experiments on the storage of eddoes and tannia (Colocasia and Xanthosoma spp) under tropical ambient conditions. Tropical Science, 24, 39.
[10] Goenaga, R., Singh, U., Beinroth, F.H. and Prasad, K. (1991) SUBSTOR—Aroid: A model in the making. Agrotechnology Transfer, 14, 1-4.
[11] Tagodoe, A. and Nip, W.K. (1994) Functional properties of raw and pre-cooked taro (Colocasia esculenta) flours. International Journal of Food Science & Technology, 29, 457-462.
[12] Bradbury, J.H. and Holloway, W.D. (1988) Chemistry of tropical root crops: Significance for nutrition and agriculture in the Pacific. Australian Centre for International Research, Canberra.
[13] Ghan Jr., H.T., Kao-Jao, T.H.C. and Nakayama, T.O.M. (1977) Anthocyanin composition of taro. Journal of Food Science, 42, 19-21.
[14] Bradbury, J.H. (1988) Chemical composition of tropical root crops. ASEAN Food Journal, 4, 3-13.
[15] Sefa-Dede, S. and Sackey, E.K.-A. (2002) Starch structure and some properties of cocoyam (Xanthosoma saggitifolium and Colocasia esculenta) starch and raphides. Food Chemistry, 79, 435-444.
[16] Gunaratne, A. and Hoover, R. (2002) Effect of heatmoisture treatment on the structure and physicochemical properties of root and tuber starches. Carbohydrate Polymers, 49, 425-437.
[17] Lawal, O.S. (2004) Composition, physicochemical properties and retrogradation characteristics of native, oxi- dised and aceteylated and acid-thinned new cocoyam starch. Food Chemistry, 87, 205-218.
[18] Eggleston, G., Omoaka, P.E. and Arowshegbe, A.U. (1993) Flour, starch and alternative (wheatless) bread-making quality of various cassava clones. Journal of the Science of Food and Agriculture, 62, 61-66.
[19] Whistler, R.L. and BeMiller, J.N. (1997) Carbohydrate chemistry for food scientists. Eagen Press, St Paul, 117-151.
[20] Onayemi, O. and Nwigwe, N.C. (1987) The effect of processing on oxalate content of cocoyam. Lebensmittel- Wissenschaft & Technologie, 20, 293-295.
[21] Owusu-Darko, P.G. (2008) Tannia (Xanthosoma saggitifolium) starch: Properties and flavour volatiles release. Ph.D. Thesis, Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow.
[22] Lim, S.T., Kasemwuman, T. and Jane, J.L. (1994) Characterization of Phosphorus in starch by 3IP nuclear magnetic spectroscopy. Cereal Chemistry, 71, 468-472.
[23] Lauzon, R.D., Shiraish, K., Yamazaki, M., Sawayama, S., Wuguyama, N. and Kawbata, A. (1995) Physicochemical properties of cocoyam starch. Food Hydrocolloids, 9, 77-81.
[24] Moorthy, S.N. (1994) Tuber crop starches. Central Crops Research Institute, Sreekariyam, Thiruvananthaapurram.
[25] Wang, L. and Wang, Y.-J. (2001) Comparison of protease digestion at neutral pH with alkaline steeping method for rice starch isolation. Cereal Chemistry, 78, 690-692.
[26] Zobel, H.F. (1988) Molecules to granules: A comprehensive starch review. Starch/Stärke, 40, 44-50.
[27] Iwuoha, C.I. and Kalu, F.A. (1995). Calcium oxalate and physico-chemical properties of cocoyam (Colocasia esculenta and Xanthosoma sagittifolium) tuber flours as affected by processing. Food Chemistry, 54, 61-66.
[28] Ramsden, L. and Ling, C.Y. (1998) Variability of non starch polysac-charides in taro. Tropical Agriculture, 75, 291-292.
[29] Jiang, G.S. and Ramsden, L (1999) Characterization and yield of arabinogalactan-protein in mucilage of taro corms. Journal of the Science of Food and Agriculture, 79, 671-674.<671::AID-JSFA233>3.0.CO;2-H
[30] Kay, D.E. (1987) Crop and product digest No. 2 root crops. 2nd Edition, Tropical Development and Research Institute, London, 380.
[31] De Castro, L.A.B., Carniero, M., MonteNechish, D.C. and de Paiva, G.R. (1992) Spatial and temporal gene expression patterns occur during corm development. Plant Cell, 4, 1549-1559.
[32] MonteNeschich, D.C., Rocha, T.L., Guimaraes, R.C., Santana, E.F., Loureiro, M.E., Valle, M. and de Sa, M.F.G. (1995) Characterization and spatial localization of the major globulin families of taro (Colocasia esculenta L Schott) tuber. International Journal of Plant Sciences, 112, 149-159.
[33] Shewry, P.R. (2003) Tuber storage proteins. Annals of Botany, 91, 755-769.
[34] Theeraslip, S., Hitotsuya, H., Nakajo, S., Nakaya, K., Nakamura, Y. and Kurlhara, Y. (1989) Complete amino acid sequence and structural characterization of the taste- modifying protein, miraculin. The Journal of Biological Chemistry, 264, 6655-6659.
[35] Guimaraes, R.I., Marcellino, L.H., Grossi de Sá, M.F. and de Castro Monte, D. (2001) A storage protein gene from taro shows tuber specific gene expressions in transgenic potato. Physiologia Plantarum, 111, 182-187.
[36] Majumder, P., Mondal, H.A. and Das, S. (2005) Insecticidal activity of Arum maculatum tuber lectin and its binding to the glyco-sylated insect gut receptors. Journal of Agricultural and Food Chemistry, 53, 6725-6729.
[37] Bezerra, I.C., de Castro, L.A.B., Neschich, G., de Almeida, E.R.P., Grossi de Sa, M.F., Mello, L.V. and Monte-Ne-schich, D.C. (1995) A corm specific gene encodes tarin, a major globular protein of taro (Colocasia esculenta, L Schott). Plant Molecular Biology, 28, 137-144.
[38] Kiran, K.S. and Padmaja, G. (2003) Inactivation of trypsin inhibitors in sweet potato and taro tubers during processing. Plant Foods for Human Nutrition, 58, 153-163.
[39] Van Damme, E.J., Goosens, K., Torrekens, S., VanLeuven, F., Verhaert, P. and Peumans, W.J. (1995) The major tuber storage protein of Araceae species is a lectin (Characterization and molecular cloning of the lectin from Arum maculatum L.). Plant Physiology, 107, 1147-1158.
[40] Yamashita, H., Theeraslip, S., Aluchy, T., Nakaya, K., Nakamura, N. and Kurlhara, Y. (1990) Purification and complete amino acid sequence of a new type of sweet protein with taste-modifying activity, curculin. Journal of Biological Chemistry, 265, 15770-15775.
[41] Duangmal, K. and Appenteng, R.K.O. (1999) A comparative study of polyphenol oxidase from taro (Colocasia esculenta) and potato (Solanum tuberosum var. Romano). Food Chemistry, 64, 351-359.
[42] Gohl, B. (1981) Tropical feeds. FAO, UN, Rome.
[43] Bradbury, J.H. and Nixon, R.W. (1998) The acridity of raphides from edible corms. Journal of the Science of Food and Agriculture, 76, 608-616.<608::AID-JSFA996>3.0.CO;2-2
[44] Hussain, M., Norton, G. and Neale, R.J. (1984) Composition and nutritive value of cormels of Colocasia esculenta (L) schott. Journal of the Science of Food and Agriculture, 35, 1112-1119.
[45] Paull, R.E., Tang, C.S., Gross, K. and Uruu, G. (1999) The nature of taro acridity factor. Postharvest Biology and Technology, 16, 71-78.
[46] Sakai, W.S., Hanson, M. and Jones, R.C. (1972) Raphides with boards and groves in Xanthosoma saggitifolium (Araceae). Science, 178, 314-315.
[47] Sakai, W.S. (1979) Aroid crops: Acridity and raphides. In: Inglett, G.E. and Charalambus, G., Eds., Tropical Foods: Chemistry and Nutrition, Vol. 1, Academic Press, New York, 265-276.
[48] Holloway, W.D., Argall, M.E., Jealous, W.T., Lee, J.A. and Bradbury, J.H. (1989) Organic acids and calcium oxalates in tropical root crops. Journal of Agricultural and Food Chemistry, 37, 337-341.
[49] Sunell, L.A. and Healy, P.L. (1979) Distribution of calcium oxalate idioblasts in corms of taro (Colocasia esculenta). American Journal of Botany, 66, 1029-1032.
[50] Fertuga, B.L. and Oluyemi, J.A. (1976) The metabolizable energy of some tropical tuber meals for chicks. Poultry Science, 55, 868-873.
[51] Gerpacio, A.L., Roxas, D.B., Uichanco, N.M., Roxas, N.P., Custudio, C.C., Mercado, C., Gloria, L.A. and Castillo, L.S. (1975) Tuber meals as carbohydrate sources in broiler rations. Proceedings of Conference Animal Feeds of Tropical and Subtropical Origin, Tropical Products Institute, London, 151-154.
[52] Moy, J.H., Shabolt, B., Stoewsand, G.S. and Nakayama, T.O.M. (1979) Processing of taro products. Journal of Food Processing and Preservation, 3, 139-144.
[53] Ravindarn, V., Sivakanesan, R. and Cyril, H.W. (1996) Nutritive value of raw and processed colocasia (Colocasia esculenta) corm meal for poultry. Animal Feed Science and Technology, 57, 335-345.
[54] Samarasinghe, K. and Rajaguru, A.S.B. (1992) Raw and processed wild colocasia corm meal (Colocasia esculenta (L.) Schott var esculenta) as an energy source for broilers. Animal Feed Science and Technology, 36, 143-151.
[55] Tang, C.S. and Sakai, W.S. (1983) Acridity of taro and related plants. In: Wang, J.K., Ed., Taro, University of Hawaii Press, Honolulu, 148-163.
[56] Liener, I.E. and Kakade, M.L. (1980) Protease inhibitors. In: Liener, I.E., Ed., Toxic Constituents in Plant Feedstuff, Academic Press, New York, 7-71.
[57] Sumathi, S. and Pattabiraman, T.N. (1979) Natural plant enzyme inhibitors. Studies on trypsin inhibitors of Colocasia antiquorum tubers. Biochimica et Biophysica Acta, 566, 115-127.
[58] Krishnasharma, K. and Pattabiraman, T.N. (1980) Natural plant enzyme inhibitors. Isolation and characterization of two amylase inhibitors from Colocasia antiquorum tubers. Journal of the Science of Food and Agriculture, 31, 981-991.
[59] Watt, J.M. and Byer-Brandwijk, M.G. (1962) The medicinal and poisonous plants of southern and eastern Africa. Livingstone, Edinburgh.
[60] Philipy, B.Q., Bland, J.M. and Evens, T.J. (2003) Ion chromatography of phytate in roots and tubers. Journal of Agricultural and Food Chemistry, 51, 350-353.
[61] Bradbury, J.H., Eghan, S.V. and Matthews, P.J. (1995) Cyanide content of the leaves and stems of edible aroids. Phytochemical Analysis, 6, 268-271.
[62] Njintang, Y.N. and Mbofung, C.M.F. (2003) Development of taro (Colocasia esculenta L. Schott) as an ingredient for food processing: Effect of gelatinisation and drying temperature on the dehydration kinetics and colour of flour. Journal of Food Engineering, 58, 259-265.
[63] Hong, G.P. and Nip, W.K. (1990) Functional properties of precooked taro flour in sorbets. Food Chemistry, 36, 261-270.
[64] Rekha, M.R. and Padmaja, G. (2002) Alpha-amylase inhibitor changes during processing of sweet potato and taro tubers. Plant Foods for Human Nutrition, 57, 285-294.
[65] Prathibha, S., Nambisan, B. and Leelamma, S. (1998) Effect of processing on amylase and protease inhibitor in tropical tubers. Journal of Food Processing and Preservation, 22, 359-370.
[66] Le Quach, M., Melton, L.D., Harris, P.J., Burdon, J.N. and Smith, B.G. (2001) Cell wall compositions of raw and cooked corms of taro (Colocasia esculenta). Journal of the Science of Food and Agriculture, 81, 311-318.<311::AID-JSFA816>3.0.CO;2-B
[67] Arnaud-Vinas, M.D.R. and Lorenz, K. (1999) Pasta products containing taro (Colocasia esculenta, L Schott) and chaya (Cnidoscuolus chavamansa L. Mcvaugh. Journal of Food Processing and Preservation, 23, 1-20.
[68] Ihekoronye, A.I. and Ngoddy, P.O. (1985) Cocoyams. In: Integrated Food Science and Technology for the Tropics, Macmillan, London, 280-281.
[69] Obiechina, O.C. and Ajala, A.A. (1987) Socioeconomic and cultural importance of cocoyam as staple food. Proceedings of First National Workshop on Cocoyam, NRCRI, Umudike, 180-184.
[70] Onwueme, I.C. (1978) Colocasia and xanthosoma. In Tropical Tuber Crops, John Wiley and Sons, New York, 199-227.
[71] Subhadhirasakul, S., Yuenyoungsawwad, S., Ketjinda, W., Phadoongsombut, N. and Faroong-Sarng, D. (2001) Study on tablet binding and disintegration properties of alternate starches prepared from taro and sweet potato tubers. Drug Development and Industrial Pharmacy, 27, 81-87.
[72] Onwulata, C.I. and Constance, R.P. (2002) Viscous properties of taro flour extruded with whey proteins to simulate weaning foods. Journal of Food Processing and Preservation, 26, 179-194.
[73] Onwuka, N. and Enneh, C. (1996) The cocoyam (Xantho-soma sagittifolium) as a potential for raw material source for beer brewing. Plant Foods for Human Nutrition, 49, 283-293.
[74] Gubag, R., Omoloso, D.A. and Owens, J.D. (1996) Sapal: A traditional fermented taro [Colocasia esculenta (L.) Schott] corm and coconut cream mixture from Papua New Guinea. International Journal of Food Microbiology, 28, 361-367.
[75] National Academy of Science. (1975) Underexploited tropical plants with promising economic values. Report of ad hoc panel of the advisory committee on technology innovation, National Academy of Sciences, Washington DC.
[76] Wang, J.K. and Nagaragan, K. (1984) An integrated taro production system for the humid tropics. In: Chandra, S., Ed., Edible Aroids, Clarendon Press, Oxford, 140-148.
[77] Griffin, G.J.L. (1979) Non-food applications of starch, especially potential uses of taro. In: Plucknett, D.L., Ed., Small-Scale Processing and Storage of Tropical Root Crops, Westview Tropical Agricultural Series, 1, 275-301.

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