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[KAMPALA] Close to the centre of the Ugandan capital Kampala, near the shore of Lake Victoria, is an area known as Luzira. In this unimposing place, two old buildings stand facing each other.

The buildings seem abandoned, but every day the space between them teems with activity. Like bees with their honey, the workers at Luzira labour to produce the raw material for one of our favourite sweets: chocolate.

The Luzira cocoa processing plant, however, is unusual in its use of plastic. In the only operation of its kind in east and central Africa, the workers at this site are harnessing the power of the sun to dry cocoa for export.

Cocoa is a major earner of foreign exchange in Uganda, fetching US$1,500 to US$1,700 a tonne — three times what Uganda gets for coffee, its main export crop.

To get the best price, quality is essential and for this the cocoa must be dried until its water content is about seven per cent of its weight. Too much moisture affects the cocoa's scent and flavour and can encourage the growth of mould.

"Cocoa beans with fungi cannot be used to produce chocolate," says Domenico Malcangio, an engineer with Italian chocolate company ICAM who led the team responsible for introducing the new 'plastics' technology at Luzira.

"This technology will solve the biggest problem of quality control," says Joseph Kimera, a technical officer at the Cocoa Development Project.

The power of plastic

Given its promise for the industry, the technique is remarkably simple. A special type of plastic sheeting that converts the sun's ultra-violet rays into infra-red is put up on an aluminium frame and the beans are spread out to dry beneath the plastic after workers have rubbed them over sieves — rubber mat-like structures — to remove any dust or mould.

The polythene sheeting produces temperatures of 50 to 60 degrees Celsius, which dries the cocoa to perfection.

"Once farmers have done proper fermentation and clean drying to ten per cent moisture content, it completes the process, bringing moisture content to between seven and seven and a half per cent," explains Kimera.

Though it is just 200 millimetres thick, the sheeting is tough enough to last for 30 to 40 years. "Ordinary plastics would be destroyed by the sun's rays in just six months," says Malcangio.

Malcangio says the structure can also withstand wind speeds of 30 to 40 kilometres per hour because the aluminium structure that holds the sheeting is flexible.

Last September, ICAM and a local agricultural exporter, JOACHIPO Commercial Enterprises, paid US$60,000 to bring the technology to Uganda.

JOACHIPO's managing director, Joseph Adhum, says that 26 tonnes of semi-dried cocoa the company bought in early November was fully dried and ready for export just two days later.

An obvious improvement

The method's temperature control means it can be used to dry other crops too. According to Adhum, it was brought in to improve the quality of coffee, vanilla, chillies and maize, as well as cocoa.

"We're experimenting with drying tomatoes and sesame seeds, by interchanging the sieves according to the sizes and shapes of seeds," Adhum explains as he spreads cocoa beans on the shelves.

Traditional cocoa harvesting and drying methods, as practised by over 90 per cent of Ugandan cocoa farmers, are basic. Harvesters simply pick the pods, extract the seeds and spread them on the ground, for sun drying. Exporters may have concrete floors for drying the beans, but this would represent a huge expense for a farmer.

In any case, drying in the open — even on floors or on tarpaulin — leaves the beans vulnerable to rain, wind or cloudy days that slow the process. Another risk during dry seasons, when the crop may be left out all night is of the beans being contaminated by livestock or wild animals.

The 'plastic' approach is an obvious improvement. The beans are protected from rain, wind and contamination, and dry under controlled conditions. The framework and material are neither bulky nor expensive, and so can be easily transported to rural areas and purchased by farmers' cooperative unions or societies.

Meeting export demands

Moreover, cocoa produced from such a hygienic process will more easily meet the agricultural and handling standards of importers in the Europe or North America.

Cocoa has been grown in Uganda for 100 years, but has never been an important crop for domestic or export markets. British colonialists introduced the species in 1903, planting it at the Botanical gardens in Entebbe, Uganda.

"It's from there that Ugandan agricultural researchers became interested in it," says John Muwanga-Musisi, coordinator for the national Cocoa Development Project.

Muwanga-Musisi says that now Uganda is producing cocoa for export, the government wants to see a rapid rise in the quality and quantity of production due to a huge market demand.

"This Italian technology comes at a critical time when we're supposed to implement the European Union market's strict Good Agricultural Practices and plant health regulations for all agricultural exports into its market to protect its consumers," says Muwanga-Musisi.

Boosting cocoa exports could lead to the Luzira experience being repeated across the country, and increasing numbers of Ugandan farmers using the power of the sun and tough plastic sheeting to dry a whole range of crops for export.