Tapioca is a starch that is used as a food thickener, perhaps most famously in pudding. The term is also used generically in some places to refer to other food thickeners, which can lead to some confusion. True tapioca is extracted from the cassava root, using a complex multi-step process that leaches out toxins in the root to get at the usable starch within. Many cultures all over the world have adopted this starch for use in their own cuisine.
Cassava is a shrub-like plant native to South America, cultivated for its edible roots. It is also known as manioc, and it has played an important rule in the cuisine of many South American peoples. Unfortunately for the people who like to eat it, cassava on its own has toxins that can be dangerous in large amounts, so the roots must be treated before they can be used in food products.
The word for tapioca comes from the Tupi language of what is now known as Brazil. It integrates ty for “juice,” pya, or “heart,” and oca, for “remove.” The Tupi word for the food is tipi'oca, in a reference to the way in which the food is extracted.
To make it, the root is pulped and washed to leave the usable starch behind. The starch is heated so that individual granules will burst, and the resulting paste is reformed into a powder, flake, or pearl form. The powder is used for things like jellies and pudding, since it dissolves well in warm water. The flakes are also used for similar applications, while the pearls are usually used whole in foods, like pearl milk tea.
The flavor is fairly neutral, making it an excellent choice of thickener for both sweet and savory foods, and it has little nutritional value. The limited nutritional value of cassava root in general has caused historical problems, especially among peoples who rely on it for a major source of nutrition. As a supplement to other foods, however, cassava is quite useful. In addition to being grown in South America, the root is also cultivated in Africa and Asia for an assortment of uses.
Classic tapioca pudding is made with whole pearls, which lend a texture to an otherwise smooth or bland pudding. The pearls become chewy and resilient when cooked, and this property is also harnessed to make boba or pearl milk tea, a popular Asian beverage. Pearl milk tea is made with large pearls mixed with fruit juice or tea, a sweetener, and milk. A specialized straw allows the drinker to suck up the tapioca along with the beverage.