Abstract

The world food, medicinal drug, and cosmetic market has been dominated until recently by synthetic colorants. Lately, however, the industry is turning more and more to natural coloring agents, thus increasing the market for these products. This project will develop the use of a specific raw material, namely the sorghum dye, on the basis of a traditional technology known for centuries in Burkina Faso and other countries of the region. The red sorghum, widely spread in West Africa, provides a red coloring matter used in dyeing fibers, leather, and handicrafts, as well as a cosmetic and food colorant. The project will study the anthocyanine pigment responsible for the red coloring of the dye obtained from the plant. Within this research, a method of analysis will be developed as well as process of extraction, which should make a product with constant quality permanently available to the consumer.

Post-Project Summary

The University of Ouagadougou researchers produced extracts of the anthocyanins contained in the sorghum used in pigment production, which they then separated and analyzed by the usual methods. They developed a reproducible method of analysis for the purpose of determining the anthocyanin content of the extracts, based on the nature of the anthocyanins present and the possible presence of interfering substances. The following parameters were studied in the laboratory: system of solvents to be used; optimum temperature and duration of extraction; relation between the quantity of solvent and the quantity of raw material; and the effect of additives on the stability and colour of the extracts. A preliminary socio-economic analysis was conducted and several potential markets for the pigments were identified (as a food colouring in the soft drink industry, for example). At the current price, the pigment producing capacity of a cultivated hectare of pigment producing sorghum would be CDA $2 880, which would represent a valuable source of revenue for the country.

Recipient Institution(s)