The Practical Herbalist

Tapioca

Plants have many interesting strategies for survival. Plants are food for animals, and there needs to be a balance in nature that allows the plants and the animals to thrive. Some plants use poison to protect the valuable parts of the plant. Herbalists pay attention to poisons as they can indicate powerful medicine as well as valuable food sources.
An interesting example is tapioca. This pearl-like gooey starch found in many desserts is a valuable food source in tropical regions. Tapioca comes from the cassava or manioc plant (Manihot utilissima). The storage root of the plant is rich in starch, similar to potato. The best growing and most valuable cassava is called a bitter cassava. It survives and reproduces well because it protects those valuable roots. The roots contain a milky juice that has a strong concentration of cyanide. This poison protects the roots from being eaten. As a result the plants are abundant. Man has learned that through simple processing of mashing, washing, and heating the root material, the poison can be removed. Processing cassava provides a valuable food source that is the staple of the diet in many regions.

Many plants have chemical defenses, most are not as toxic as the cassava. Those that are less toxic can be sources of useful medicines. In this case of cassava, the poison does not provide a medicine, but rather protects a food source for the humans that survive on it. It is interesting to think that the holiday desert you may be eating was made possible by one of the deadliest poisons known to man.