Cocoa is indigenous to the Amazon region of South America, and, during the first years of the twentieth century, the southern region of Bahia provided the perfect conditions for its growth. The cocoa-producing region of Bahia is composed of 92 municipalities and Ilheus and Itabuna are its main centres. This region accounts for 87% of the national production of cocoa in Brazil, currently world’s the second largest producer of cocoa beans. Cocoa is also produced in about 50 other countries, with Nigeria and Ghana being major producers.
The vast majority of this production is exported to countries like Japan, the Russian Federation, Switzerland and the United States; half of this is sold as processed products (chocolate, vegetable fat, chocolate liquor, cocoa powder and butter) and the rest is exported as cocoa beans.
Process Overview
The industrial method for processing cocoa involves several stages. It begins with the storage of the raw material in adequate sheds, where it undergoes fumigation to prevent the proliferation of rodents and insects. Next, the process of cleaning the grains begins in order to remove any foreign objects or residues. Then all cocoa beans are dried out to extract excess moisture until an ideal level is reached. The next stage is the cracking of the grains in order to separate the skin from the core, followed by the roasting stage, which consists of the heating of the inner part of the grain.
The resulting product, which is in the shape of small particles known as “nibs”, is subject to a process of grinding (crushing), thus becoming a liquid paste, which in turn is strained and solidified in refrigeration chambers and sold as paste.
Most grinding companies normally separate the liquor through a process of pressing it until the fat is extracted and converted into two final products: cocoa butter and cocoa cake. The cake is packed in solid pieces while the cocoa butter is filtered, deodorized, cooled in refrigeration chambers and later packaged.
Hazards and Their Prevention
Although, the processing of cocoa is usually automated in such a way that it requires little manual contact and a high level of hygiene is maintained, the great majority of the employees in the industry still are exposed to a variety of occupational risks.
Noise and excessive vibration are problems found throughout the production line since, in order to prevent the easy access of rodents and insects, closed sheds are built with the machinery suspended on metal platforms. These machines must be subjected to proper maintenance and adjustment routines. Anti-vibratory devices should be installed. Noisy machinery should be isolated or noise reduction barriers should be used.
During the fumigation process, tablets of aluminium phosphate are utilized; as these come in contact with humid air, phosphine gas is released. It is recommended that grains remain covered for periods of 48 to 72 hours during and after these fumigation sessions. Air sampling should be done before re-entry.
The operation of grinders, hydraulic presses and drying machinery generate a great deal of heat with the high levels of noise; the high heat is intensified by the type of construction of the buildings. However, many safety measures can be adopted: use of barriers, isolation of the operations, implementation of schedules of working hours and breaks, availability of liquids to drink, use of adequate attire and the appropriate acclimatization of the employees.
In the areas of finished products, where the average temperature is 10 °C, staff members should wear appropriate clothing and have working periods of 20 to 40 minutes. The process of acclimatization is also important. Rest breaks in warm areas are necessary.
In the operations of product reception, where storage of raw materials and all finished products are packaged, ergonomically inadequate procedures and equipment are common. Mechanized equipment should replace manual handling where possible since moving and carrying loads can cause injuries, heavy articles can hit employees and injuries can result from the use of machinery without proper guards.
Procedures and equipment should be evaluated from an ergonomic point of view. Falls due to slippery floors are also a concern. In addition, there are other activities, like the cracking of the grains and the grinding and production of cocoa powder, where there are high levels of organic dust. Adequate dilution ventilation or local exhaust systems should be installed; processes and operations isolated and segregated as appropriate.
A rigorous programme of environmental risks prevention is highly recommended, in addition to the regular system of fire prevention and safety, adequate guarding of machinery and good standards of hygiene. Signs and informational bulletins should be posted in highly visible places and equipment and devices for the personal protection should be distributed to each worker. In maintaining machinery, a lockout/tagout programme should be instituted to prevent injuries.