Feedback: Here are the six ways to curb cassava poisoning

To increase the efficiency of cyanide removal in cassavas, it requires a combination of the processing techniques, for example, during fermentation, you can combine with soaking and drying to ensure efficient removal of the cyanide. FILR PHOTO | NMG

What you need to know:

  • Cassava utilisation is limited because of the presence of cyanide, which causes poisoning. Various cassava tubers and varieties vary in the amount of cyanide content.
  • The process reduces the amount of cyanide to considerable levels. The starch is an important ingredient in medicine and food formulations.
  • The best irrigation method for saline water is drip because it allows the water to be used and it also reduces salinity by maintaining a moist environment around the roots and this enables leaching of the salts.

HOW TO PREVENT CASSAVA POISONING

Iā€™m a farmer who grows cassava for consumption. I would like to know methods to prevent cassava poisoning.
John Aluku, Busia County

Cassava utilisation is limited because of the presence of cyanide, which causes poisoning. Various cassava tubers and varieties vary in the amount of cyanide content.

The root which is edible contains lower cyanide compared to the peels. Therefore, some of the methods that can be used to reduce the toxicity of these cassava tubers are:

Peeling: It is the most commonly used method in preparing cassava for human consumption. Hence, it involves peeling the outer cover (peels) of the tuber, which contain a considerable amount of cyanide.

Boiling: Common method that can be used, however, the percentage reduction of cyanide depends on the boiling time, volume of water and tuber piece size.

Therefore, for effective removal, you need to cut the tuber into small sizes for efficient removal of cyanide. Moreover, soaking the tubers in water for 24 hours before boiling is a necessary step that can reduce the cyanide content to a considerable amount.

Drying: First, you need to reduce the tuber sizes and make them uniform shaped and dry them in the sun. The temperatures the tubers will be exposed to will effectively reduce the cyanide content to a lower level.

Fermentation: This is a common method that is practised among various communities in the country. During fermentation, microbial activity will reduce the cyanide content to considerable amount.

This will result in a product of higher texture quality and improved palatability. Moreover, it will upgrade the nutritive value and reduce other toxic substances found in cassava tubers.

Starch extraction: This technique involves wet milling of the washed cassava roots, followed by washing the starch from the fibrous mass using vibrating screen.

The starch is sedimented in settling tanks and sun-dried. Busia County government announced plans to set up the plant.

The process reduces the amount of cyanide to considerable levels. The starch is an important ingredient in medicine and food formulations.

Steaming, baking, and frying: Deep-fat frying fresh cassava pieces or chips is also another method that can be used in reduction of cyanide content in cassava. Most cyanide reduction in this process occur during the steaming stage.

Moreover, this reduction is also experienced during baking of cassava tubers into various products.

Combination of several processing methods: To increase the efficiency of cyanide removal, it requires a combination of the processing techniques, for example, during fermentation, you can combine with soaking and drying to ensure efficient removal of cyanide.

Cyprian Syeunda,
Department of Dairy,
Food Science and Technology,
Egerton University.

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BEST IRRIGATION SYSTEM WITH BOREHOLE WATER

I am Mwaringa. I drilled a borehole on my farm in Mariakani to a depth of 160 metres. I intend to irrigate five acres either through drip or furrow irrigation.

The borehole has an output of 1,500 litres per hour. I am done with both chemical and bacteriological analysis of the water. Please advise me on: ā€”

Is my water too saline to use for irrigation? If not, which high value crops can be safely irrigated using saline water?

Beets, bell pepper, broccoli, cabbage, sukuma wiki, loquats, spinach and tomatoes have high salt tolerance and can be grown with saline water. Carrots, cauliflower, lettuce, peas, potatoes, squash and sweetcorn have moderate salt tolerance.

Which is the best irrigation system between drip or furrow, considering the quality of the water?

The best irrigation method for saline water is drip because it allows the water to be used and it also reduces salinity by maintaining a moist environment around the roots and this enables leaching of the salts.

Carol Mutua,
Department of Crops, Horticulture and Soils, Egerton University.

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CROPS THAT CAN DO WELL IN SIAYA

I would like to venture into any type of agribusiness but I am somehow confused on what to start with. I live in Siaya and I have got three acres.

Though rainfall in this area is not that much, I have a deep well that supplies me with more than enough water that I can do irrigation with. Please advise.

Yayo Otieno

Watermelon, sorghum, groundnuts, onions, oranges, mango, sweet potato and indigenous vegetables like spider plant (saget), nightshade (managu) and amaranthus (terere), pawpaw, lemons, butternut, okra, pumpkin leaves and fruits, African birds eye chillies, bell pepper and eggplant will do well in the county.

Carol Mutua,
Department of Crops, Horticulture and Soils, Egerton University.