A modest grater means safer and
quicker cassava in Uganda
"Before, we used to cut the cassava into pieces, peel it, wash it, and leave it to dry in the sun for a day," said the farmer. "Then we covered it for four days with banana leaves or a mat. Afterwards, we scraped off the mould, pounded the pieces, and dried them again. This used to take a week." With their new grating technology, the women of this northern Ugandan village can now have their cassava ready in just one day.
"It is all very simple," said Ellen Psomgen, head of the Bweyale United Women's Association. "The cassava root is peeled, washed and grated. Then we place it in a container and cover it for three hours. We make a funnel from papyrus, and we push the pulp through it with a stick, squeezing out the water with the toxins until what is left is dry. We put the rest on an iron sheet in the sun. The process takes a day, not a week like it used to."
It's all in the grating. "There are two cassava types here. It's fine to eat the sweet cassava varieties immediately," said Sicco Koligjn, an agricultural engineer with FAO. "It's the bitter varieties that are dangerous. They contain cyanide that must be extracted before the cassava is eaten." Grating breaks down the cassava so that the cyanide can easily be drawn off.
The process not only saves time, but can save lives. Cassava is the most important crop for food security in a region often battling drought and famine, so waiting a week to eat is not always possible. When hunger strikes, food is needed immediately, and people often skip part of the process, with potentially deadly results. Eaten without processing, bitter cassava can cause stomach problems, a type of paralysis called konzo, and in some cases even death.
But farmers here cannot rely on sweet cassava alone. First, some of them are migrants from other parts of the country and cannot tell the difference between the sweet and bitter varieties. And second, the survival of sweet cassava is at stake as a virus sweeps the region.
According to experts, African Cassava Mosaic Virus Disease - mosaic for short - is moving quickly across West-Central Africa and could reach northern Uganda soon. "It has not quite spread this far, but we are told it is coming fast," said Ellen Psomgen of the women's association. As the virus advances, ways must be found to tap into bitter cassava resources quickly. By introducing cassava grating technology, FAO hopes to speed up detoxification and improve the region's food security.
The grating technique used here is not revolutionary. It has been tried successfully in West Africa and Brazil. What it does is help local farmers feed themselves at no risk when there is precious little alternative to a possibly deadly food source.
The graters come in several sizes. The smallest is a hand-held model for individual households, and the largest a motorized version that can feed an entire village. But the technology, however beneficial, is not without its problems. It is still being fine-tuned and adapted to local conditions. "We are not yet very confident," said Psomgen. "It has to be made a little safer, because we can hurt our fingers if we are careless."
"And it is not too good for commercial uses, because we cannot process a large amount at a time. Even if we could, we would have no way of marketing it. But we are working on improvements ourselves, here among the women, and the important thing is that people like the grater. It is faster now, which means we can eat when we are hungry."
Resolving the problem of producing cassava in commercial quantities is considered a priority. "The cassava flour made from the grated cassava is very clean and brings in more money," said Gabriel Nkuzaalwe, the local agricultural extensionist and district cassava coordinator. "But it takes time to prepare so you cannot produce more than what you need for a day."
Efforts are also being made to develop new varieties that can better resist the virus, but so far they remain unpopular because of their taste. Nkuzaalwe said that by rejecting the new varieties, farmers were making themselves vulnerable. "They continue planting the old cassava which could succumb to the virus. If the crop is wiped out, there is no cassava, and so there is no food," he said.
Finding ways to produce cassava commercially and preventing the spread of mosaic are just two of the many activities under the FAO post-harvest project Improvement in Food Crop Post-Harvest Systems at Farmer's Level, which tries to prevent food from being lost between the time a crop is harvested and when it is consumed. Project activities in other parts of the country include training local farmers to build silos and granaries to store crops, solar dryers for vegetables and spices to generate income, and cooperation with entomologists to develop natural pesticides.
One of Africa's poorest nations, with a GDP per caput of US$182, Uganda has an agricultural economy in which 90 percent of the population depends on some kind of farming for survival. Yet, with its crushing debt burden, the government spends less than a tenth of its budget on agriculture. Clearly, securing food for the vast majority of Ugandans remains a challenge, especially in the drier north and east.
In an impoverished country such as Uganda, a modest hand-held grater could hold the key to food security for an individual or an entire family. Not bad for a little rectangular frame covered with a sheet of tin punched full of holes.
22 May 1997