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Post-harvest losses aggravate hunger

Improved technology and training show success in reducing losses

Photo: ©FAO/A. Conti
Making metal silos for grain storage.
2 November 2009, Rome - Significant amounts of the food produced in developing countries is lost after harvest thereby aggravating hunger, FAO said today. The agency stressed that with adequate investment and training food losses could be drastically reduced.

The causes of post-harvest losses, which some estimates suggest could range from 15 to as high as 50 percent of what is produced, are manifold. These include: harvesting at an incorrect stage of produce maturity, excessive exposure to rain, drought or extremes of temperature, contamination by micro-organisms and physical damage that reduces the value of the product.

Crops also lose value because of spillage, damage from inappropriate tools, chemical contamination or rough handling (including heat build-up) during harvesting, loading, packing or transportation.

Food losses contribute to high food prices by removing part of the supply from the market. They also have an impact on environmental degradation and climate change as land, water, human labour and non-renewable resources such as fertilizer and energy are used to produce, process, handle and transport food that no one consumes.

Safeguarding harvested produce

Many of the losses, which can be significantly reduced if there is adequate training, occur because of erroneous transport and packing practices. FAO, collaborating with the World Bank and others, has trained thousands of people in three continents to handle harvested food properly.

For example, in Kenya, where mycotoxin contamination of grain staples is of major concern, FAO, together with the Ministry of Agriculture, has provided technical training for stakeholders involved in food production.

Another major problem, further highlighted during the 2008 food crisis, is the inadequate and insecure storage facilities in many developing countries—it is here that interventions by FAO and collaborating donor agencies can make a significant impact.

A recent FAO project in Afghanistan, funded largely by Germany, provided household metallic silos to around 18 000 beneficiary households. The project was designed to reduce post harvest losses by improving storage facilities and enhancing the technical capabilities of local tinsmiths in silo construction. The silos are hermetically sealed, thus protecting the food stored within from pests, rodents, birds and fungi. Another advantage is that of allowing produce to be kept for long periods with no loss of quality.

The effect was immediate. Participating farmers began using the silos to store cereal grains and grain legumes and shortly thereafter reported higher incomes and longer storage possibilities. Because of the silos, post harvest losses fell from between 15 and 20 percent to less than one or two percent. In addition, the technical training to tinsmiths meant an additional 4 500 silos were manufactured locally and sold to other farmers.

In Guinea—where between 70 and 80 percent of the population depends on agriculture for its livelihood—a project was designed to reduce post harvest losses from their usual level of around 20 percent. Some 100 silos, ranging in capacity from 100 to 1800 kilograms, were distributed. Dozens of artisans were trained in the construction and installation of silos. As a result, farmers were able to reduce losses in their grain stocks to a minimum and defer sales until better market conditions prevailed.

All in all, more than 45 000 silos have been installed or built in 16 countries and more than 1 500 professionals, technicians and craftsmen have been trained in constructing and handling them.

To make technologies such as these silos accessible to small farmers, interventions also are needed in other areas. In many developing countries farmers cannot afford the materials to build the silos, so FAO has set up revolving funds and loans to facilitate the diffusion of better storage containers. Other interventions involve establishment of innovative institutional mechanisms such as warehouse receipt systems.

Impact of quality standards

Despite these apparent successes, post-harvest losses still represent a problem in many countries. In Western supermarkets, fruits and vegetables are graded according to generally acceptable trade standards so if produce is bruised, wilted, unripe, misshapen, of incorrect size or just generally unsightly it will not be put on the shelves. There is often no alternative market for such produce, which is then thrown away. This is presently less of a problem in developing countries.

With world population expected to near its peak in 2050 and greater urbanization in many developing countries, meaning higher-value food will have to be moved over longer distances, greater efforts are needed to reduce significantly food losses in the entire food chain. At the very least, there will have to be significantly greater investment in cold and dry storage infrastructure and first-stage processing equipment.