Origin and distribution The cocoa tree is a native of the Amazon basin and other tropical areas of south and central America, where wild varieties still grow in the forests, but the cocoa growing area has extended to the Caribbean and Africa.
Most of the worldâ€™s cocoa is grown in a narrow belt 10 degrees on either side of the equator. Cocoa trees grow well in humid tropical climates with regular rains and a short dry season.
The trees need even temperatures between 21-23 degrees Celsius, with a fairly constant rainfall of 1000-2500mm per year. Different types of cocoa are grown in various areas. In Australia, Cadbury uses high quality cocoa beans sourced from Ghana, Nigeria, Cote Dâ€™Ivore and Asia.
In Africa, cocoa was first planted in Ghana in 1879. Ghana is now a major world producer. There are 40 to 50 million people worldwide who depend on cocoa for their livelihood. Setting up a plantation Every year, Lwanga pots over 60,000 seedlings during the dry season (October and November) using the top forest (alluvial) soils.
The composition of the soil has to be neutral, neither acid nor alkaline. The seedlings take six months to grow before they are transplanted at the onset of the first rains (in March-April-May) or in the second rains (October-November-December).
The spacing should be 3m x 3m (10ftx10ft) and the planting hole 2ft x 2ft deep and wide. Manure can be applied if it is available. About 435 seedlings are needed for an acre. Once the seedlings are established, the farmers must watch them closely for signs of distress.
Cocoa trees need a shade, therefore, they should be planted under mature tall tropical trees or intercropped with bananas and coffee trees. If the land does not have any other plant on it, interplant cocoa with beans and Musizi trees to control wind and strong tropical sunlight at a spacing of 20ft x 20ft (32 trees per acre).
After-care In the forest, prune out the broad tree branches and slash the undergrowth. Carry out shallow or hand weeding or slashing around the plant. Be careful not to harm the roots. When the cocoa canopy establishes, it will suppress grass or any plant beneath it.
It is important to prune the cocoa tree during the early stages. Cocoa requires filtered sunlight through trees. Sustainable management of shade trees like Musizi, grumixana, sapote and breadfruit allows the farmer to earn extra income from timber and fruits. It also maintains or increases the cocoa bean production each year.
Harvesting Cocoa starts flowering and putting on pods at two-and-half years and ripens in the third year. In the fifth year, it increases pods, depending on the management. July is the first peak harvesting season and November-December the second.
But every fortnight, farmers harvest cocoa pods. A cocoa tree reaches peak production in 10 years and will continue producing pods for an additional 12-13 years. Shade-grown cocoa trees can produce pods for 75 to 100 years or more. Under-ripe pods have low cocoa butter content, while over-ripe ones may contain microbes, which affect the fermentation process and the chocolate flavour.
The pods grow as green or maroon pods on the trunk and the main branches. Shaped like an elongated melon, the pods ripen to a golden colour. It is important to keep the cocoa plantation grounds well-weeded such that the fallen pods can be seen and collected. Major diseases Cocoa cannot be infected by bacteria wilt.
However, Lwanga says the most formidable obstacle to cocoa farmers is Nzirugaze, a parasite plant that grows on the branches of the cocoa trees. Processing and fermentation After harvesting, cocoa pods are split open.
The beans are removed along with pulp, put in buckets, carried to the fermentation boxes and covered with fresh banana leaves. Lwanga explains that each of his boxes â€˜A and Bâ€™ accommodates 700kg. After three days, the beans are scooped out from â€˜Box Aâ€™ and put in â€˜Box Bâ€™ for two days. Then, back to â€˜Box Aâ€™ for two more days to attain full fermentation uniformity.
The beans are stirred everyday using a wooden shovel. Avoid using a metal shovel as this affects flavour development. After the seventh day, a bean-cut-test is done to ascertain whether the beans have fully fermented. If the inside of the bean has turned to the mahogany-brownish colour with a chocolate flavour, then they are ready.
If the bean is purplish inside, leave it for another day. When the beans are ready, they are put out in the sunlight to dry on a raised platform/rack, tarpaulin or mats. Cocoa beans are fermented to stop them from germinating and to develop the chocolate taste through a special chemical reaction called the â€˜maillardâ€™ reaction.
After fermentation, the beans have a moisture content of 55% to 60%. Drying should reduce the moisture content to 7% to allow safe storage before roasting. The beans take between four to seven days to dry, depending on the intensity of the sunlight. During this time, foreign matter like cocoa husks, fragments and placentas are sorted out. Dried beans are packed in sisal bags, stitched and stored on racks.
The store should be free of oils and perfumes. Cocoa is hygroscopic. It absorbs foreign bodies easily. Cocoa is now ready for chocolate making.
Compiled by John Kasozi
How to grow, process cocoa