Page 271 - Algae Anatomy, Biochemistry, and Biotechnology

254 Algae: Anatomy, Biochemistry, and Biotechnology

FIGURE 7.1 Harvesting of Arthrospira bloom from Lake Kossorom. (Courtesy of Dr. Gatugel Abdulqader.)

holes, and the surface of the biomass is smoothed with the palm of the hand. Within a few minutes,
almost all of the extracellular water will have seeped out of the biomass, and the dihe ´ is then cut into
8–10 cm squares, 1–1.5 cm thick, and removed from the holes as soon as it is firm enough for the
squares to be handled without breaking (Figure 7.2). The drying is completed on mats in the sun.
Dihe ´ is traded in the local markets, and in the markets of the main towns of Chad, from where it can
also be taken across the borders of Chad to Nigeria, Cameroon, and other countries. It is estimated
that about 40 tons of dihe ´ are harvested from this lake Kossorom every year, corresponding to a
local trading value of more than US$100,000, which represents an important contribution to the
economy of one of the poorest nations in the world.
Dihe ´ is mainly used to prepare la souce, a kind of vegetable broth served with corn, millet, or
sorghum meal, which occasionally can have fish or meat as additional ingredients. Well-dried dihe ´
is crumbled in a bowl either by hand or with a mortar and pestle; cold water is then added to dis-
perse the lumps, and the suspension is strained through a fine sieve to remove such solid impurities
as sticks, grass, and leaves. The suspension is poured away from most of the sand that settles to the
bottom of the bowl. The cleaned dihe ´ is cooked for 1–1.5 h, which further disperses the lumps,
yielding a blue-green broth that still contains small amounts of plant debris and sand. This broth
is transferred into a bowl, left to settle for 5–10 min to allow sedimentation of any residual
sand, strained very carefully once more, and then poured over saute ´ed onions. Salt, chili
peppers, bouillon cubes, and gombo (Hibiscus esculentus) are added, and la souce is then simmered
and occasionally stirred until cooked.
A minor utilization of dihe ´ is as remedy applied onto wounds to speed up the healing process, or
as a poultice to soothe the pain and reduce the swelling of mumps.