How it began
On the northeastern shore of Lake Chad, in what is now Chad, women customarily gather a blue-green alga, a variety of spirulina, known locally as dihé. Kanembu women have passed the method from mother to daughter. The United Nations Food and Agriculture Organization (FAO) reports that the harvesters are mostly poor women of the low "blacksmith" caste. The sources describe the practice as customary and give no date for its beginning.
How it works
The alga forms at certain times of year in shallow brackish pools near the wadis at the end of the rainy season. It needs daytime temperatures of 35 to 37 degrees Celsius falling to 15 to 20 degrees at night. Women collect the green water and filter it directly on the sandy ground, where the sand draws off the liquid and the sun dries the layer into a thin biscuit. The dried cake is later crumbled and cooked into a sauce. Dihé is rich in protein, iron and beta-carotene.
What changed first
In 2007 FAO began a project worth 1.4 million dollars, funded by the European Union, that showed the women how to harvest more efficiently and hygienically and how to process, package and market the product. By 2010 ten tons of improved dihé had been produced and sold through pharmacies and groceries in Chad, generating profits of 50 million CFA francs for 500 women.
Where it stands today
Spirulina is grown commercially elsewhere as a dietary supplement. The coordinator of the FAO project in Chad said the naturally produced dihé was about 100 times cheaper than spirulina sold in developed countries, and estimated that output could rise tenfold without upsetting the ecological balance of the pools. FAO noted that further testing and international certification would be needed before wider marketing.
