Knowledge for Development

Feature articles

New postharvest treatments: Expanding markets for tropical fruits

For the last twenty years or more, it has been possible to consume fresh fruit from other continents on a daily basis. The tropical fruits and vegetable sector was late to develop, only reaching maturity when the preservation of freshness, an essential requirement of the market, was no longer an issue. Reduction in transportation times and the use of refrigeration led to the preservation of quality of imported produce.


Adding value to Jamaican herbs and spices: reducing postharvest losses and expanding market opportunities

Jamaica has a rich history of utilizing herbs and spices in the preservation of food, a tradition of both its native Tainos and its African slaves. In addition to improving the shelf-life of meat, fruits and vegetables, the unique flavours and aromas that resulted endeared the island to the people from cooler climates. Spices were also very valuable items that for millennia formed an integral part of the trade regime. Early Europeans were enamoured with the pungent and fragrant flavours. Christopher Columbus, for example, is credited with having taken back allspice (pimento) to Europe from the Caribbean. The spice trade was lucrative, resulting in aromatics such as nutmeg, ginger and black pepper being plied between the West Indies and Europe by early traders and settlers. While most important spices originated in Asia and Africa, the Caribbean islands have been said to have more potent flavours than their counterparts.


Sustainable Small-Scale Poultry Production: Are Local Feeds a Viable Option for the Pacific Region?

The lack of regional small-scale feed manufacturing plants, high cost of imported feed and cheap imports are holding back the development of the smallholder poultry sector in Pacific countries. As there are adequate supplies in some regions of locally produced feed ingredients (cassava, sweet potato, coconut, maize), the prospect for alternative feedstuffs is in the semi-commercial or family poultry units. For these sectors, profitability rather than maximum production is the objective, and alternative feedstuffs can make a useful contribution in poultry feeding.In his article, Glatz examines four feeding strategies to produce effective poultry rations that are in line with the regional availability of feed resources. With a complete ration formulation using local ingredients, egg production was significantly lower in birds fed the local mix ration compared to the commercial ration. Testing free-choice feeding, the birds showed the capacity to regulate their intake according to their physiological requirements, provided that the three food groups were readily available. Using a mix of concentrate with local ingredients, birds fed a 50/50 sweet potato / low-energy concentrate or a 50/50 cassava / high-energy concentrate diets were able to reach market weight in due time. A 70/30 sweet potato / low-energy concentrate diet was effective only in the more suitable environment of the Western Province of PNG. Diluting commercial broiler finisher with 20-40% copra meal resulted in similar growth as the 100% broiler finisher control diet (inclusion of 60% copra meal resulted in somewhat less acceptable growth). Poultry farming in the Pacific using local feeds can be competitive and achieve 30% feed cost savings when mini-mill equipment is readily available and small-scale regional feed manufacturing centres (producing 5-10 tonnes/week) are built where local feed supply is plentiful.


Analysis of the post-harvest knowledge system in Ghana: case study of cassava

In this article, Gloria Essilfie writes a detailed account of the post-harvest system of cassava in Ghana. Based on a case  study on gari processing, Essilfie documents the different stages of the production chain and identifies hotspots for post-harvest loss. She finds that losses are minimal during  the actual gari production chain and recommends that further research  to determine on-farm losses (during the wet season especially) and at the level of the distributors and markets. In terms of research and training capacity for (cassava) post-harvest science, technology and innovation, Essilfie's account of (para-) governmental and academic institutions shows Ghana possesses sufficient and adequate resources to tackle the losses from field to market. Essiflies also highlights the fact that the profitability of the gari value chain in Ghana is dependent on the cassava varieties grown by farmers: higher yielding, pest resistant and starchier varieties can prevent monetary losses at the processing stage.Finally, Essilfie explains that Ghana's Food and Agricultural Sector Development Policy (FASEDEP II) provides for specific interventions in the cassava production and processing sector that would consolidate the value chain, guarantee food security and economic growth. For example, FASEDEP II lists variety improvement, up-to-date knowledge/protocols for extension, machinery and equipment, private sector participation and  market access as priorities. Specifically for the gari processing plant under study, Essilfie recommends that: farmers be taught to use high yielding varieties and improved cultivation techniques; processors be trained in meeting hygiene and food safety standards for both the local and export markets; industrial extension services be strengthened as well to better guide the processors; links to international markets and overseas branding be developed and sustained. 


Analysis of the post-harvest knowledge system in Trinidad and Tobago: case study of pumpkin

In this article, Majeed Mohammed conducts an assessment of the pumpkin post-harvest handling system in Trinidad and Tobago. The study also looks at the human, infrastructural and institutional capacity and the information/data gaps for better policy formulation. Mohammed provides an estimation of post-harvest losses of pumpkin at various market outlets at critical stages in the handling system during dry and wet seasons in Trinidad and Tobago  and notes that post-harvest losses varied according to growing season and type of market outlet. Dry and wet season pumpkin postharvest losses were highest at export markets and lowest at wholesale markets, for example. Each step in the handling system (harvest, transportation, curing, sorting, packaging, and storage) is assessed and causes for losses identified. It is clear that multiple handling along the marketing chain influences the cumulative levels of deterioration in quality, and ultimately the magnitude of post-harvest losses. Mohammed provides an in-depth account of post-harvest training, research and outreach institutions in Trinidad and Tobago, and detailed descriptions of each institution's specific function and roles in knowledge creation and capacity development. While various academic departments, international development organisations and public agencies all provide for post-harvest research and training, major hindrances affecting the flow of information still exist. In Trinidad and Tobago, the best sources of information for producers and marketers are 'trial and error', garden shops, and fellow professionals, while it was found that research institutes and farmers training centres only reach around 15% of farmers. Extension, mainstream media and associations have no significant impact. As the government of Trinidad and Tobago is building packing houses across the country and infrastructure for the development of value-added products, Mohammed also recommends better extension for farmers and processors: demonstrations on pumpkin farms at harvest time, development of standards, handling procedure and best practices, introduction of low cost processing technology, etc. Participants at a follow-up workshop clearly identified extension and training as the priority for the sector.   


Analysis of the post-harvest knowledge system in Senegal: case study of the rice sub-sector

In this new article, Fallou Sarr reflects on the post-harvest knowledge system for rice in Senegal. He note that rice occupies a prominent place in Senegal's economy and in food consumption for both urban and rural households. Since independence, rice consumption has increased by almost 1,000%, reaching 1 million t of milled rice. Paddy rice production is the responsibility of farmers in irrigated areas and rain-fed areas However, the collection of paddy rice, in irrigated areas, is an activity undertaken by traders, rice millers and farmers while, in rain-fed areas, it is mainly carried out by women and children (more than 90% in the Southern area) and with carts (70% to 80%, in the Central area). Factories find it difficult to secure large quantities of paddy rice in  a single collection area in the Senegal River valley, Sarr acknowledges that there is a clear difference between both rice cultivation systems and this is also reflected in post-harvest losses. However paddy drying is critical for both systems with losses ranging from 5 to 10%. Irrigated systems face two additional critical issues: paddy rice harvest (ill-adapted harvesters) and drying (insufficient drying areas). On the other hand in rain-fed systems, threshing losses, which is mainly manual, represents the stage where most post-harvest losses are recorded (40 %). Sarr emphasizes three intervention areas for improving the post-harvest knowledge system; research, government & universities and regional organizations.For research, Sarr recommends that they systematically assess post-harvest losses at all stages of the rice value/supply chain, to indicate critical points and the best ways to address them; study, experiment and disseminate local knowledge on rice post-harvest handling (rice conservation/storage) and adapt technological innovations for greater efficiency, effectiveness and accessibility (harvester, thresher, sorter). With respect to the government and universities, he recommends that a national programme entirely focused on improving rice post-harvest systems (equipment, infrastructure, processing, training, organisation, marketing, access to credit) be developed. For regional organisations such as CORAF/WECARD, Sarr recommends that they include more projects specific on post-harvest treatment in their food crops programmes.