(introduction...)

Yams are the staple food of many peoples of Africa.

Yams are eaten fresh, or are treated and preserved.

Most varieties of yams, especially the wild species that are not cultivated, contain a poison (dioscorine). But this poison is removed by washing the yams several times in salt water and by cooking them well.

This is why yams must never be eaten raw, but only when they are thoroughly cooked.