Understand how cassava can release cyanide and learn about the risks of improper preparation.
Cassava is found on tables from Brazil to Vietnam, but few know that, if improperly processed, the root can produce cyanide.
This toxic cassava, if poorly prepared, has already caused outbreaks and even the neurological disease konzo.
The good news? With simple care, the danger disappears and the flavor remains.
What makes cassava potentially dangerous?
The “bitter” variety concentrates cyanogenic glycosides.
When the root is grated or bitten, enzymes release cyanide — the same poison famous in spy stories.
Without proper boiling or fermentation, the compound remains in the food.
Why do cases of poisoning occur?
Lack of fuel or water for cooking in poor regions.
Emergency harvests during times of famine.
Lack of knowledge of traditional preparation techniques.
Konzo: A Little-Discussed Disease
In African communities with protein-poor diets, repeated consumption of poorly processed cassava leads to konzo.
Cyanide affects the nervous system, causing sudden weakness in the legs and possible permanent sequelae.
How to Make Cassava Safe
1. Peel thoroughly
The peel holds most of the toxins. Remove it completely
2. Soak or Ferment
Grate or peel the root and cover it with clean water for 24–48 hours. In Northern Brazil, farinha d’água (cassava flour) follows this method.
3. Cook until tender
Boiling for at least 20 minutes breaks down the toxic molecules. Raw roots should never be consumed.
4. Combine with protein
The body detoxifies cyanide better if amino acids are available. Include eggs, fish, or legumes in the meal.
