Improved processing of shea nuts in northern Ghana

Partners:

Technology Consultancy Centre of the University of Science and Technology, Ghana
Intermediate Technology Transfer Unit (ITTU), Ghana

Problem:

The Shea tree grows across a wide swathe of Sahelian Africa, from Senegal to Ethiopia. Its fruit is gathered from the wild and is highly valued by local communities, not only for the economic and dietary value of the cooking oil, but also for the fruit pulp, bark, roots and leaves, which are used in traditional medicines and for the wood and charcoal, used for building and cooking. 

The production of shea butter is an important income earning activity for many rural women in northern Ghana and for some it is their only source of income.  However, the traditional method of processing is an extremely arduous and time consuming activity, which uses large quantities of water and firewood, scarce natural resources in northern Ghana and other shea production areas. 

Achievements:

The project developed and evaluated an improved extraction process using a bridge press, which offers:

• reduction in processing time for 25kg shea kernels from 9.5 hours to 3.25 hours;
  
  
• significant decrease in water usage from 90 litres to 1.7 litres;
  
  
• complete elimination of fuel wood.

The press is operated manually and requires minimal effort to operate.  Labour productivity is certainly increased, and the drudgery associated with the traditional process is, at least, partially alleviated.  After the oil has been extracted the residue is removed from the press as solid blocks which can be sun-dried and used as a fuel.  No further processing of the oil is necessary. 

The quality of the extracted butter, in terms of moisture content and free fatty acid levels, was independently verified by a number of manufacturers, both domestic and international, and found to be well within the quality specifications of major European buyers.  However, financial analysis of the bridge press technology showed that despite significant increases in labour productivity over traditional methods of extraction, the profitability derived from the current scale and technical efficiency of the technology is dependent on market prices for the butter.

Further information   John Orchard E-mail: J.E.Orchard@gre.ac.uk  Telephone: +44 (0)1634 883741 Fax +44 (0)1634 883386