manioc

Manioc, or cassava, is a woody perennial shrub cultivated for its large, tuberous roots. Manihot esculenta is a major carbohydrate staple in tropical regions and is grown widely in Africa, Asia, and Latin America. The roots are rich in starch and are typically white or pale yellow; the non-edible bitter varieties contain higher levels of cyanogenic compounds. In many cuisines the leaves are cooked as a leafy vegetable.

Taxonomy and varieties: Manioc belongs to the Euphorbiaceae family. Cultivars are commonly grouped as sweet or bitter, reflecting their cyanogenic glycoside content. Sweet types produce less toxin and require shorter processing; bitter types yield higher toxin levels and require extensive detoxification.

Cultivation: propagated from stem cuttings; tolerates poor soils and variable rainfall; once established, it can be drought-tolerant. Time to harvest depends on variety and environment, typically eight to 24 months. Common pests and diseases include cassava mosaic disease and cassava brown streak; management relies on clean seed material and integrated pest control.

Processing and uses: to detoxify, roots are peeled, grated, and subjected to soaking, fermenting, drying, or cooking; these steps reduce cyanide content to safe levels. Processed products include cassava flour, tapioca, and starch; in many countries cassava is also eaten directly after cooking. Leaves are consumed as a vegetable when properly prepared.

Safety and nutrition: cassava is high in calories but generally provides little protein; raw tubers and leaves contain cyanogenic glycosides that can be toxic if not processed properly. With suitable processing, cassava is a safe and important food source in many tropical diets.