Another interesting innovation showcased during the Postharvest Congress and Exhibition was Nigerian Dr Iheanacho Okike’s machine for drying and grading cassava peels.
The innovation, which produces livestock feed from the peels, won the second prize. Dr Okike is a research scientist with the International Livestock Research Institute in Ibadan.
With this technology, you can cut the drying of cassava peels from three days to one. Cassava peels are said to contain about 8 to 10 per cent dry matter and 62 per cent soluble carbohydrates. It is low in fibre, at 16 per cent, with 6.5 per cent crude protein.
When processed, the peels contain 2,200 kilo calories per kilogramme of dry matter compared to 3,000 kilo calories per kilogramme dry matter of maize.
“Cassava peels have been found to be a suitable substitute in animal feeds. It is two thirds the energy value of maize but lower in protein content,” he said. Yet, researchers report that 50 million tonnes of cassava peels are being wasted and treated as an environmental nuisance.
However, the peels contain poison and have to be dried gradually to reduce toxicity. Dr Okike’s drying technology, which involves crushing and rapidly de-watering cassava peels, is key to jumpstarting the cassava business.
There are two varieties of cassava. The sweet variety contains zero cyanide, meaning it can be consumed directly. The bitter variety, which is higher in cyanide content, must be processed to lower this before consumption.
“Grating, de-watering and drying are key processes in breaking up cyanide in cassava and ensuring it is safe for consumption. And those same processes have been followed in pushing this technology to the livestock sector for animal feeds,” the researcher said.
With livestock production expected to more than double in the next 40 years, transforming cassava peels into high quality feed holds huge potential for African economies, especially Kenya, struggling to meet the rapidly rising demand for animal-source products.
“In poultry keeping, for example, processed cassava peels can substitute 25 per cent of maize without lowering the performance. For growing pigs it can provide as far as 75 per cent replacement of maize without lowering performance,” he said.
Traditionally, drying the peels with all its liquid content that makes up 70 per cent of the peels when wet, takes longer. What the scientist and his colleagues have developed has reduced the drying of cassava peels from three days to one. The resulting dry cake is sun-dried.
If you put 100 kilos of grated material into the press, by the time you have pressed to about five minutes you will only have 50 kilos left,” the researcher said.
“Traditionally, drying cassava peels takes about three to four days during the dry season and become more complicated during wet seasons,” he said. The innovation has also solved the problem of drying the cassava peels that usually affects the energy content when used in feed manufacturing industry.
FULL STORY INSIDE SMART FARMER MAGAZINE ISSUE 36