Traditional processing of peanuts in Ghana

Abstract

A nationwide survey was conducted in Ghana In 1995 to study the traditional peanut processing industry. A total of eighty-five processors from all the ten regions of the country were interviewed. The survey revealed that the traditional peanut processing industry in Ghana is female dominated with the major products being peanut butter, peanut oil, "tunkusa" (partially defatted peanut butter) and "kulikuli" (fried tunkusa). Peanut butter which is used for the preparation of soups and stews in Ghana ranked first and was produced by ninety eight percent of the respondents. Several varieties of peanuts are cultivated in the country and of these the "China" variety was most preferred for the preparation of peanut butter because of it`s high oil content, palatability, availability, and ease of dehulling. Other varieties used were "Manipintar", "Kulikuli", Dagarasime", and "Kpedevi". The processing of peanut kernels into butter in Ghana is essentially a batch process consisting of six main unit operations. These are sorting, roasting, dehulling, winnowing, milling and packaging. The survey revealed that the milling operation was the only fully mechanised operation in the production of peanut butter. Roasting of peanuts was found to be mechanised to an extent with the use of a roaster in some parts of the country. All other operations in the production of peanut butter were carried out manually. The quantity of peanuts processed at widely from as low as 2.5kg to 200kg. Frequency of processing also varied from everyday to once a month. Majority of the processors however processed peanut butter either once or twice a week and most processors only purchased the amount of peanuts required for a single batch processing and as such did not store the raw material for any considerable length of time. Majority (84%) of processors roasted peanuts using washed sea or river-bed sand in either earthenware, aluminium or cast-iron pans over a fire or heat source. Wood fuel was commonly used. A rotating drum roaster was used in the Northern regions of the country and was preferred to the manual method of roasting because of it`s higher efficiency with regards to burning losses, and the processors' reduced exposure to direct heat during roasting. Various parameters were relied upon to determine whether peanuts were cooked during the roasting process. These were ease of peeling with the fingers, colour, scent, taste, and in most cases a combination of these parameters were used. The survey revealed three methods for the dehulling of roasted peanuts. These were rubbing between the hands or fingers, gentle pounding using a mortar and a pestle, or rubbing with a wooden board on tables, or on jutesacks or even on cemented floors. The latter method was found to be the most widespread one used in the country. Milling of roasted, dehulled and winnowed peanuts was by the use of the disc attrition mill and all the processors preferred the product very finely milled. Most processors were able to tell the fineness of the product by simply rubbing an amount between the fingers or by visual observation during the milling process. Occasionally, salt, water, pepper and onions were added either during or after the milling process to improve the taste of the soup or prolong the shelf-life of the product. The survey revealed that no sophisticated packaging is given to peanut butter in the country. The product is usually retailed directly from enamel or plastic bowls using either spoons or the the bare hands into polyethylene bags for customers. A batch of peanut butter could last for as long as three weeks although majority of the processors sold their product within a week. Peanut processors in the country face several problems, the most important ones being the drudgery and health problems encountered In the roasting, dehulling and winnowing of peanuts during the preparation of peanut products. This was evident In the fact that all the processors interviewed were prepared and willing to adopt new techniques or methods of processing and even expressed the desire to pay a fee for the improved technologies. Finally this survey revealed several lapses during the processing and handling of the products and intensive education is needed to protect the health of consumers of these peanut products