Tapioca Pudding by Dobrin Isabela, via Flickr
By Kate Prengaman
Here’s a question: What do tapioca pudding, bubble tea, Brazilian slash and burn agriculture, and subsistence farming in Africa have in common? The simple answer is in botanical latin: Manihot esculenta. Called manioc, cassava, mandioca, yuca, tapioca, and sago, people world-wide eat foods produced from the starchy tubers of the M. esculenta, a member of the botanically diverse Euphorbiaceae, which includes poinsettias. According to the UN, it’s the third most important food in the tropics, after rice and corn. However, it’s also poisonous- two cyanide compounds, linamarin and lotaustralin, require careful processing before the tubers can be eaten.
A pile of tubers, by Luciano Ghersi on Flickr
I first met M. esculenta in 2005, when I lived in the Brazilian Amazon as part of a study abroad program focused on the interaction between human and environmental issues. I spent a week working with a family of slash and burn agriculturalists on a small tributary of a tributary of the Amazon River, outside Manaus. This dense rainforest, with small clearings for homes and farming carved by hard work, was a fitting place to meet M. esculenta, which is called manioc there. The plant was originally domesticated in tropical Brazil, and like many common foods with South America origins, it was later exported to Africa and Southeast Asia.
A young Manioc plant in the Amazon, by Colonos, via flickr
This is labor intensive agriculture. My entire host family, even the small children, worked to produce manioc flour. After the plants grow large enough, they are pulled up to harvest the root tubers, which look similar to big, long potatoes, with a very rough skin. You can’t just eat the tubers, due to the cyanide. Instead, they peel the tubers, grind them into a rough pulp, soak the pulp, squeeze dry, and then toast it in giant metal tubs over a wood fire. The soaking and heating remove most of the cyanide, to produce a flour that can be sold. In many African countries, in contrast, the tubers are often soaked for several days to ferment, which removes the cyanides, before cooking.
The small, translucent balls of tapioca that we eat here in the U.S. are produced from the starch that separates from the soaking pulp after grinding. The starch gelatinizes, breaking down the crystalline structure, and sticking together into clumps, when heated to about 60 degrees C. These clumps of moist starch is pressed through a sieve to create small “pearls” of tapioca. Called boba in many Asian cultures, the balls are common in drinks, like “bubble tea.” The pearls need to be soaked to rehydrate. In Brazil, they taught me to add the pearl tapioca to my hot coffee, let it soak, and then add the sugar and milk, and eat it for breakfast with a spoon. You can eat your cereal and coffee in one single step with this method! This was my frequent breakfast, and it’s not bad, but I can’t say I’ve continued the habit since I returned.
Despite the incredible variety of culinary uses of M. esculenta, it remains the staple crop of the poor. The agriculture is very labor intensive, not conducive to industrialization. The Food and Agriculture organization of the U.N. sponsors research for improving the subsistence farmer’s ability to produce this stable food. Much of this research has focused on developing genetically modified M. esculenta, which has met with resistance both from farmers and food activists. The starch production for export is mainly in Nigeria, Brazil, and Thailand. Nutritionally, M. esculenta is considered to be mainly a source of calories only. According to the FAO “GLOBAL CASSAVA DEVELOPMENT STRATEGY”
Its composition shows 60-65 percent moisture, 20-31 percent carbohydrate, 0.2-0.6 percent ether extracts, 1-2 percent crude protein and a comparatively low content of vitamins and minerals. However, the roots are rich in calcium and vitamin C and contain a nutritionally significant quantity of thiamine, riboflavin and nicotinic acid. Of its carbohydrate, 64-72 percent is made up of starch.
So, it’s not exactly empty calories, but it’s not a nutritional powerhouse either. The people who rely on these calories work hard to produce them, and for good reason. It grows well in the tropics and it is pretty tasty; as tapioca pudding, as a flour in baked goods, fried like potatoes, or the course flour (farofa in brazil), toasted and served as a topping to rice and beans or feijoada.
I’ll add my favorite tapioca pudding recipe when I get home to my cookbook tonight!
Eating Science 