Both tapioca starch and corn starch are great options whether you are looking for a thickener or are on a gluten-free diet and need a wheat flour substitute. Both are also effective thickeners in large part because their flavors are neutral, which means that they work without affecting the flavors in your dish. While their function is similar, they do have some differences. If you are trying to decide which one to use, consider the factors below.
How do tapioca starch and corn starch differ?
Tapioca starch differs from corn starch in terms of its source. Corn starch is sourced from corn, as you may have guessed; tapioca starch comes from the cassava root. Cassava root is a starchy tuber, which means that tapioca starch has more in common with other root starches like potato starch and arrowroot than it does with a grain starch like corn starch.
The two have strong similarities such as the fact that they both thicken liquids effectively; however, they differ in terms of how they handle heat. Corn starch stands up well to high heat and long cooking times while tapioca starch works best when added at the end of cooking. It will lose its thickening ability if subjected to heat for too long.
The appearance of the final product will also differ as tapioca starch will also give you a more glossy and transparent final product, whereas cornstarch can make for a murkier liquid with a matte surface. Liquids thickened with corn starch also tend to get spongy when frozen and thawed.
Neither of these starches is a nutritional powerhouse but tapioca holds a small edge over corn starch since it has higher concentrations of a few nutrients. Tapioca has more calcium and vitamin B-12 than corn starch.
If your recipe requires one, can you use the other?
In most cases, these two starches are interchangeable as thickeners. You will still have to be mindful of the differences above. You cannot use cornstarch to thicken a dish that contains a high concentration of acids or of sugars.
With tapioca starch, you cannot use it a thicken a dish that will be cooked past the point where it gels or it will thin out.
When should you use tapioca starch and when should you use corn starch?
Use corn starch as a replacement for tapioca starch in dishes like fruit pies that have to be cooked for long periods after being thickened. You should avoid using corn starch in dishes that contain lemon, lime or orange juice.
Use tapioca starch as a corn starch substitute in dishes that benefit from a transparent and glossy appearance or that have a strong acidic component. You should also use it to thicken dishes that you intend to freeze and in dishes that you want to be thickened quickly and where further cooking will not be required. Tapioca starch will retain its texture when the dishes are thawed; corn starch may become gummy.
Tapioca starch is the better option for those dealing with a corn allergy who want to avoid genetically modified foods. Most corn in the US is grown from genetically modified seeds while the cassava used to make tapioca starch is not genetically modified. Note also that allergies to cassava are rarer than allergies to corn.