My first lesson in Ghanaian cooking

The take-home message here is: be sure to prepare your cassava properly!!!

I had been trying to figure out how to cook some Ghanaian foods, and had no clue what cassava was.  So, I Googled it, and was led to a Wikipedia article on cassava.  Started out with a lovely botanical picture, then a photo of peeled cassava roots in a bowl.  Fair enough.  Then came trouble - I started reading...here's what I found, directly from Wikipedia:

"

Processing and toxicity

Cassava root peeled

The leaves cannot be consumed raw because they contain free and bound cyanogenic glucosides. These are converted to cyanide in the presence oflinamarase, a naturally occurring enzyme in cassava. The roots, however, are eaten raw everywhere in Africa. Cassava varieties are often categorized as either "sweet" or "bitter", signifying the absence or presence of toxic levels of cyanogenic glucosides. The so-called "sweet" (actually "not bitter") cultivars can produce as little as 20 milligrams of cyanide (CN) per kilogram of fresh roots, whereas "bitter" ones may produce more than 50 times as much (1 g/kg). Cassavas grown during drought are especially high in these toxins.^[8] [9] One dose of pure cassava cyanogenic glucoside (40 mg) is sufficient to kill a cow.

Societies which traditionally eat cassava generally understand that soaking and/or cooking is necessary to avoid getting sick.^{[citation needed]} However, problems do occur—konzo (also called mantakassa) is a paralytic neurological disease associated with several weeks of almost exclusive consumption of insufficiently processed bitter cassava. Dr Jasson Ospina, an Australian plant chemist, has developed a simple method to reduce the cyanide content of cassava flour.^[10] The method involves mixing the flour with water into a thick paste and then letting it stand in the shade for five hours in a thin layer spread over a basket, allowing an enzyme in the flour to break down the cyanide compound. The cyanide compound produces hydrogen cyanide gas, which escapes into the atmosphere, reducing the amount of poison by up to five-sixths and making the flour safe for consumption the same evening. This method is currently being promoted in rural African communities that are dependent on cassava.^[11]

For some smaller-rooted "sweet" varieties, cooking is sufficient to eliminate all toxicity. The larger-rooted "bitter" varieties used for production of flour or starch must be processed to remove the cyanogenic glucosides. The large roots are peeled and then ground into flour, which is then soaked in water, squeezed dry several times, and toasted. The starch grains that float to the surface during the soaking process are also used in cooking.^[12] The flour is used throughout the Caribbean. The traditional method used in West Africa is to peel the roots and put them into water for 3 days to ferment. The roots then are dried or cooked. In Nigeria and several other west African countries, including Ghana, Benin, Togo, Ivory Coast, and Burkina Faso, they are usually grated and lightly fried in palm oil to preserve them. The result is a foodstuff called 'Gari'. Fermentation is also used in other places such as Indonesia (see Tapai). The fermentation process also reduces the level of antinutrients, making the cassava a more nutritious food.^[13]

The reliance on cassava as a food source and the resulting exposure to the goitrogenic effects of thiocyanate has been responsible for the endemic goitres seen in the Akoko area of southwestern Nigeria.^[14]

"

(I do recommend reading the rest of the Wikipedia article - there's a lot of fascinating stuff about cassava!)

So, difficult as it is to fathom, one of Ghana's most important staple foods can poison you with CYANIDE if not prepared properly!  Luckily, the article also states that people in cassava-dependent societies generally understand the need to prepare it so as not to cause problems - but still, a good thing to know ahead of time.  I think I will NOT be making cassava as my first Ghanaian recipe - yams, anyone???