Q: How healthful is cassava flour? I’ve been noticing it as an ingredient in some products, but I thought cassava was poisonous.
A: It’s not toxic when prepared properly, but it’s also not the most nutritious flour. Cassava, also called yuca or manioc, is a starchy tuber that originated in South America. Shaped like an elongated potato, it’s covered with a hairy, brown, bark-like skin enclosing soft, dense white flesh. Cooking cassava not only makes it palatable but also eliminates cyanide compounds that can form in the raw vegetable, mostly in the peel.
The flour—a staple in Africa, South America, and Asia, where it’s used in breads, cakes, and other foods—is made from the whole tuber that has been peeled, dried, and ground.
In recent years, as demand for gluten-free wheat alternatives has grown, U.S. manufacturers have been incorporating this grain-free flour—with its mild taste and soft powdery texture—into some processed foods including crackers and pretzels.
Also available is the flour itself, which can replace wheat in a one-to-one ratio in many recipes or can be used as a thickener. Some companies state on their websites how they process the tuber to remove the toxins.
Cassava flour is high in carbohydrates and provides only small amounts of nutrients like potassium, magnesium, and vitamin C, with brands varying in fiber content (0 to 3 grams per ¼-cup serving, depending on the variety, age, and size of the cassava used). Note that tapioca flour (known as tapioca starch) also comes from cassava, but it consists only of the starch extracted from the tuber.
If you’re looking for a more nutritious gluten-free flour—or just a more healthful flour overall—better bets are those made from quinoa, teff, amaranth, buckwheat, or garbanzo beans, for instance, which generally have more fiber, protein, and nutrients, though they may not all work well in some recipes due to their stronger flavor and coarser texture.
This article first appeared in the UC Berkeley Wellness Letter.
Also see Ancient Grains: A Guide.