The Post-Harvest and Value Addition Group works on durable and perishable crops after harvest to reduce losses, enhance financial or nutritional crop-value, and assure food safety. Research ranges from the fundamentals of storage and preservation of quality throughout the marketing chain, to food-science aspects of agro-processing and responses of consumers to new food products.

Achievements

Achievements include: development of a reliable technique for predicting risk to farmers of attack by Prostephanus truncatus, a devastating stored-grain pest in Africa, and successful application of the technique in Ghana, thus allowing farmers to safeguard their valuable harvest; development of an innovative method for small-holders in sub-Saharan Africa to protect their limited grain stocks against insect damage by using diatomaceous earth (DE), and proven feasibility of exploiting local DE deposits to replace synthetic organophosphate-based insecticides; and development and validation of improved cassava processing systems. Improved handling, storage and marketing methods for sweet potato, an increasingly important urban food as well as a vital food in times of drought, were adopted and promoted to end users as part of the CGIAR HarvestPlus Challenge Program. Novel methods were developed to test acceptability of food products to low-income consumers, based on price, nutritional value and sensory preference. Improved understanding of variation of storability amongst sweet potato cultivars has enhanced the breeding programmes of the International Potato Centre.

In addition to research in developing countries, the group is collaborating with East Malling Research (EMR), a Kent based research institute with an international reputation for horticultural research, to establish the Produce Quality Centre as a centre of excellence for UK based research on fresh produce quality. Together the two institutes provide the widest range of expertise and the best facilities for post-harvest research in the UK. The Produce Quality Centre (PQC) benefits from the expertise and resources of both institutes, bringing together experts in the production, storage, marketing and supply of temperate, tropical and sub-tropical crops.

Future Plans

The team's future research strategy includes: use of refined behavioural analysis techniques in studies of insect pests of grain, to identify new options for pest management without synthetic pesticides; studies of food safety in the informal food sector of developing countries, to improve quality and safety in a sector vital for employment of poor people; investigating food and energy security to improve sustainability of rural livelihoods in semi-arid developing countries reliant on renewable natural resources; and developing optimum approaches for uptake of post-harvest value-addition in cassava (supported by Bill and Melinda Gates Foundation and EC) and bio-fortified food crops (with HarvestPlus Challenge Program); support to the horticulture sector in managing quality and waste.

Staff

Dr Louise Abayomi
Dr Aurelie Bechoff
Dr Richard Colgan
Dr Rick Hodges
Dr John Orchard
Dr Debbie Rees
Dr Tanya Stathers
Prof Keith Tomlins
Prof Andrew Westby

Key project websites:

• C:AVA�Cassava Adding Value for Africa
• Science and Technology for Enhancing the Contribution of Tropical Root Crops to Development in ACP countries
• Gratitude (Gains from Losses of Root and Tuber Crops)
• Produce Quality Centre

Examples of Recent Publications

Tomlins, Keith, Owori, Constance, Bechoff, Aurelie, Menya, Geoffrey and Westby, Andrew (2012) Relationship among the carotenoid content, dry matter content and sensory attributes of sweet potato. Food Chemistry, 131 (1). pp. 14-21. ISSN 0308-8146

Meenakshi, J.V., Banerji, A., Manyong, Victor, Tomlins, Keith, Mittala, Nitya and Hamukwala, Priscilla (2012) Using a discrete choice experiment to elicit the demand for a nutritious food: Willingness-to-pay for orange maize in rural Zambia. Journal of Health Economics, 31 (1). pp. 62-71. ISSN 0167-6296

Hassan, Sally, Colgan, Richard, Paul, Mathew J., Atkinson, Christopher J., Sexton, Amy L., van Dolleweerd, Craig J., Keshavarz-Moore, Eli and Ma, Julian K-C. (2012) Recombinant monoclonal antibody yield in transgenic tobacco plants is affected by the wounding response via an ethylene dependent mechanism. Transgenic Research. ISSN 0962-8819 (print), 1573-9368

Bechoff, Aur�lie, Poulaert, Marie, Tomlins, Keith I., Westby, Andrew, Menya, Geoffrey, Young, Stephen and Dhuique-Mayer, Claudie (2011) Retention and bioaccessibility of �-carotene in blended foods containing orange-fleshed sweet potato flour. Journal of Agricultural and Food Chemistry, 59 (18). pp. 10373-10380. ISSN 0021-8561 (print), 1520-5118 (eISSN)

Bechoff, Aur�lie, Westby, Andrew, Menya, Geoffrey and Tomlins, Keith I. (2011) Effect of pretreatments for retaining total carotenoids in dried and stored orange-fleshed-sweet potato chips. Journal of Food Quality, 34 (4). pp. 259-267. ISSN 1745-4557

Hodges, R.J., Buzby, J.C. and Bennett, B. (2011) Postharvest losses and waste in developed and less developed countries: opportunities to improve resource use. The Journal of Agricultural Science, 149 (S1). pp. 37-45. ISSN 0021-8596 (print), 1469-5146

Rembold, F., Hodges, R., Bernard, M., Knipschild, H. and L�o, O. (2011) The African Postharvest Losses Information System (APHLIS): an innovative framework to analyse and compute quantitative postharvest losses for cereals under different farming and environmental conditions in East and Southern Africa. Project Report. Publications Office of the European Union / European Commission - Joint Research Centre - Institute of Environment and Sustainability (JRC-IES), Luxembourg.

Tortoe, C., Orchard, John, Beezer, A. and Tetteh, J (2011) Application of radial basis function network with a Gaussian function of artificial neural networks in osmo-dehydration of plant materials. Journal of Artificial Intelligence, 4 (4). pp. 233-244. ISSN 1994 5450

Adebayo, K., Abayomi, L., Abass, A., Dziedzoave, N.T., Forsythe, L., Hillocks, R.J., Gensi, R., Gibson, R.W., Graffham, A.J., Ilona, P., Kleih, U.K., Lamboll, R.I., Mahende, G., Martin, A.M., Onumah, G.E., Orr, A.W., Posthumus, H., Sanni, L.O., Sandifolo, V. and Westby, A. (2010) Sustainable inclusion of smallholders in the emerging high quality cassava flour value chains in Africa: challenges for agricultural extension services. Journal of Agricultural Extension, 14 (1). pp. 1-10. ISSN 1119-944X

Amjad, M., Iqbal, J., Iqbal, Q., Nawaz, A., Ahmad, T. and Rees, D. (2010) Effect of packaging material and different storage regimes on shelf life and biochemical composition of green hot pepper fruits. In: X International Controlled and Modified Atmosphere Research Conference. ISHS Acta Horticulturae 876, 1 (876). ISHS, Leuven 1, Belgium, pp. 227-234. ISBN 978-90-66055-53-7

Cheema, M.U.A., Rees, D., Westby, A. and Taylor, M. (2010) Hormonal control of sprouting of sweetpotatoes in storage. In: ISHS Acta Horticulturae. International Society for Horticultural Science (ISHS), Leuven, Belgium, pp. 173-177. ISBN 978-90-66052-06-2