AS  Vol.5 No.12 , October 2014
Effect of Curing Treatments on Seven Key Farmers’ Yams (Dioscorea spp.) in Ghana
ABSTRACT
Curing of freshly harvested yams (Dioscorea spp.) is a process for wounded yams during harvest to heal. In this work the effectiveness of straw, polypropylene and jute sack on curing of seven key farmers’ yam varieties over a duration of 7, 14 and 21 days was studied. Seven key farmers’ yam varieties identified as Pona, Lariboko, Dente, Mutwumudoo, Serwah belonging to D. rotundata, Matches and Akaba belonging to D. alata were studied under different curing treatments. The percentage weight loss of yam tubers varied among the treatments over curing period. Curing under jute sack showed all yam varieties had weight losses less than 2.0%, within 7 days of curing. Five different varieties had weight loss less than 2.0% except Dente under the straw treatment. Mutwumudoo variety showed the highest water loss (8.4%) for polypropylene sheet and 6.9% for Lariboko in the control treatment. During 7 days curing the control and polypropylene treatment did not support yam curing. After 14 days of curing of tubers, similar tends were observed as in 7 days curing. After 14 days of curing under jute sack, percentage weight loss of the tubers ranges from 2.0% - 3.7%. In the straw treatment, the percentage weight loss ranges between 1.0% - 4.7% in all other varieties except Dente (D. rotundata) (8.2%). Polypropylene sheet treatment showed the highest percentage weight loss in Mutwumudoo variety (18.4%). A similar trend was observed for the yam tubers cured for 21days as percentage weight loss of tubers under jute sacks was 2.5 – 9.8%. Curing temperature and humidity ranged between 27&degC - 40&degC and 87% - 100% rh for yam tubers under the three different treatments of polypropylene, jute and straw. However, the control treatment recorded lower humidity of 60% - 80% rh. Curing material, duration, climatic conditions and yam varieties influenced curing and Serwah variety, which is a D. rotundata is the best bet yam variety to cure under jute sack for 7, 14 and 21 days of curing.

Cite this paper
Tortoe, C. , Dowuona, S. , Dziedzoave, N. and Rees, D. (2014) Effect of Curing Treatments on Seven Key Farmers’ Yams (Dioscorea spp.) in Ghana. Agricultural Sciences, 5, 1119-1128. doi: 10.4236/as.2014.512122.
References
[1]   Akanbi, C.T., Gureje, P.O. and Adeyemi, I.A. (1996) Effect of Heat-Moisture Pre-Treatment on Physical Characteristics of Dehydrated Yam. Journal of Food Engineering, 28, 45-48.
http://dx.doi.org/10.1016/0260-8774(95)00027-5

[2]   Ng, N.Q. and Ng, S.Y.C. (1994) Approaches for Yam Germplasm Conservation. Proceeding of the 5th Triennial Symposium of the International Society for Tropical Root Crops-Africa, Kampala, 22-24 November 1992, 135-140.

[3]   Akissoe, N., Hounhonigan, J., Mestres, C. and Nago, M. (2003) How Blanching and Drying Affect the Colour and Functional Characteristics of Yam (Dioscorea cayenensis-rotundata) Flour. Food Chemistry, 82, 257-264.
http://dx.doi.org/10.1016/S0308-8146(02)00546-0

[4]   Ene, L.S.O. and Okoli, O.O. (1985) Yam Improvement: Genetic Considerations and Problems. In: Osuji, G.O., Ed., Advances in Yam Research, Anambra State University of Technology, Enugu, 343-360.

[5]   Food and Agriculture Organization (FAO) (1985) Production Year Book 38. FAO, Rome, Italy.

[6]   Food and Agriculture Organization (1987) Dossier. Root and Tubers, Their Role in Food Security. The Courier No. 101. FAO, Rome, 62-65.

[7]   Green, K.R. and Simons, S.A. (1994) “Dead Skin” on Yams Dioscorea alata Caused by Colletotrichum gloeosporioides. Plant Pathology, 43, 1062-1065.
http://dx.doi.org/10.1111/j.1365-3059.1994.tb01660.x

[8]   Mishra, D., Mishra, A.B. and Ruth, G.C. (1989) Fungal Rots of Colocasia, Yam Beet and Carrot in Orissa Markets. Orissa Journal of Agriculture Research, 2, 156-159.

[9]   MEDA (2011) Ghana Yam Market, Sub-Sector and Value Chain Assessment. Final Report for The Bill & Melinda Gates Foundation, 13th May 2011.

[10]   MoFA (2012) Statistics, Research and Information Directorate (SRID). Ministry of Food and Agriculture, Accra.

[11]   Food and Agriculture Organization (FAO) (2012) Statistics of the Food and Agriculture Organization of the United Nations.

[12]   Hahn, N.D. (1989) The African Farmer and Her Husband. In: Deutsche Stiftung Fur international Entwicklung (Dse) (Edi.): Roots Tubers and Legumes, Report of the Expert Meeting, Bonn, 71-93.

[13]   Lynam, J.K. (1991) The Development Potential of Root Crops in Africa. Entwicklung und Ländlicher Raum, 1, 8-12.

[14]   Booth, R.H. (1974) Post-Harvest Deterioration of Tropical Root Crops: Losses and Control. Tropical Science, 16, 49-63.

[15]   Demeaux, M. and Vivier, P. (1984) Methodes moderns de conservation des ignames. L’Agronomie Tropicale, 39, 184-191.

[16]   Bautista, O.K. (1990) Postharvest Technology for Southeast Asian Perishable Crops. University of the Philippines, Los Banos.

[17]   Thompson, J. (1972) Storage and Transport of Fruit and Vegetables in the West Indies. Proceedings of the Seminar /Workshop on Horticultural Development in the Caribbean, Matarin, 12-15 March 1972, 170-176.

[18]   Hayma, J. (1982) The Storage of Tropical Agriculture Products. Agrodok 31. ACP/EEC, Wageningen, 73 p.

[19]   FAO (1990) Action Programme for the Prevention of Food Losses, Improving Post-Harvest Handling, Storage and Processing of Root and Tuber Crops. Food and Agriculture Organization, Rome.

[20]   Been, et al. (1977) Yam Curing for Storage. Acta Horticulturae, 62, 311-316.

[21]   Jenkins, P.D. (1982) Losses in Sweet Potato Stored under Local Conditions in Bangladesh. Tropical Science, 24, 17-28.

[22]   Passam, H.C., Read, S.J. and Rickard, J.E. (1976) Wound Repair in Yam Tubers: Physiological Processes during Repair. New Phytology, 77, 325-331.
http://dx.doi.org/10.1111/j.1469-8137.1976.tb01522.x

[23]   Walter, W.M. and Schadel, W.E. (1982) A Rapid Method of Evaluating Curing Progress in Sweet Potatoes. Journal of the American Society for Horticultural Science, 107, 1129-1133.

[24]   Walter, W.M. and Schadel, W.E. (1983) Structure and Composition of Normal Skin (Periderm) and Wound Tissue in Sweet Potatoes. Journal of the American Society for Horticultural Science, 108, 909-914.

[25]   Nnodu, E.C. (1987) Pit-Curing Technique for Prolonging the Shelf Life of Yam Tubers. In: Terry, E.R., Ed., Tropical Root Crops, Root Crops and the African Food Crisis, Nigeria, 140-142.

[26]   Kushman, L.J. and Wright, F.S. (1969) Sweet Potato Storage. USDA Agriculture Handbook No. 358, 44 p.

[27]   Tortoe, C., Obodai, M., Amoa-Awua, W., Oduro-Yeboah, C. and Vowotor, K. (2008) Effectiveness of Three Different Storage Structures and Curing Process for the Storage of Sweet Potato (Ipomea batatas) in Ghana. Ghana Journal of Agriculture Science, 41, 227-236.

[28]   Rees, D., Van Oirschot, Q.E.A. and Kapinga, A. (2003) Sweet Potato Post-Harvest Assessment: Experiences from East Africa. Natural Resources Institute, Chatham, 122 p.

[29]   Passam, H.C. (1977) Sprouting and Apical Dominance of Yam Tubers. Tropical Science, 19, 29-39.

[30]   Passam, H.C., Read, S.J. and Rickard, J.E. (1978) The Respiration of Yam Tubers and Its Contribution to Storage Losses. Tropical Agriculture Trinidad, 55, 207-213.

 
 
Top