Cornstarch, Arrowroot, & Starches: What's the Difference? (2024)

Summer’s extreme heat may take the starch right out of you. But it’s the time of year to reach for one of the common cooking starches—cornstarch, arrowroot, tapioca, or potato starch—to thicken your berry pies, crisps and cobblers, garden-vegetable stir-fries, and other foods. Why might you choose to use one kind of starch over theother?

What is aStarch?

Just a few teaspoons of any cooking starch will thicken loose puddings andsauces.

All starches work when the starch molecules absorb and trap liquid, then swell as they’re heated. The amount of starch used determines the degree ofthickening.

To prevent any of these powdery starches from lumping and clumping in a sauce, stir the starch first into a little cool liquid until it’s smooth, then add the slurry slowly to your sauce or filling and whisk it in as it heats. For a pie filling, pudding, or other recipe calling for sugar, mix the powdered starch with the sugar before adding it to distribute the starch evenly throughout themixture.

We tend to think of common kitchen starches as roughly interchangeable, but their different molecular structures give them different cooking properties. That’s why it’s a good idea to keep small amounts of each onhand.

You can divide cooking starches into two maingroups:

1. Grain starches (wheat, corn,oats)
2. Root starches (arrowroot, potato,tapioca)

We’ll focus on the four types of cooking thickeners: cornstarch, arrowroot, potato starch, and tapioca. All aregluten-free.

Cornstarch

Cheap and available in most American supermarkets, cornstarch is made from corn (maize) grain. Specifically, it’s obtainedby removing and refining the endosperm from cornkernels.

Besides showing up in the familiar box in the baking aisle, you’ll find it (sometimes in “modified” form) as an ingredient in commercial baked goods, frozen foods, ice cream, salad dressings, low-fat meats, and more. Half of the billions of pounds of cornstarch produced each year goes into the manufacture of corn syrup. It’s also used in paints, pharmaceuticals, adhesives, medical products, building materials, cosmetics, and textile and paper manufacturing, among tens of thousands of other industrial uses.

As a thickener, cornstarch is the go-to for manyrecipes.

• It holds up to simmering and thickens at a higher temperature than the rootstarches.
• Cornstarch is usually used to thicken at the beginning of cooking—as you would do with a macaroni & cheese or a traditional beefstew.
• It’s especially good at thickeningdairy products—it doesn’t turn slimy in cream sauce or cheesesauce.
• It’s clear when hot but opaque, matte-like,and cloudy when cold. This is problematic with berry pies because the sauce needs to be clear, whether hot orcold.
• However, cornstarch would be great for a stir-fry because it’s clear whenhot.
• Don’t use cornstarchin recipes that contain acidic ingredients (lemon juice, vinegar, citric acid, wine), as the acid may break down the starch molecules, leaving a thin, waterysauce.
• Don’t use cornstarch in dishes you plan to freeze and reheat because the food turns spongy (Use one of the root starches below if you plan to freeze yourfood).
• Cornstarch can lend a “starchy” cereal-like taste. Keep stirring and bring the sauce to a full boil, then lower the heat and allow it to simmer for a couple of minutes to allow the cornstarch to lose its starchy flavor. If you need to reheat a sauce made with cornstarch, do it slowly over lowheat.

See 15 surprising uses for cornstarch around the house!

RootStarches

Arrowroot, made from the rhizomes (tubers) of tropical plants, has almost no flavor of its own andthickens at a much lower temperature thancornstarch.

• Root starches do not hold up at high temperatures, so they are best used to thicken sauces toward the very end ofcooking.
• Arrowroot starches work well with pie fillings and sauces, adding a crystalclear, shimmering sheen and a silkier mouthfeel.
• However,arrowroot does not thicken like cornstarch, so it should not be used in a pie that needs to be thick enough to slice (e.g.,coconut creampie).
• Arrowroot freezes and thawswithout change, unlikecornstarch.
• Arrowroot has a more neutral taste; it doesn’ttaste “starchy” like grain starches (cornstarch,flour).
• Don’t use it for dairy-based sauces—it turns themslimy.
• Choose arrowroot if you’re thickening an acidicliquid.

Potato starch has many of the same benefits as arrowroot.As its name implies, potato starch is refined from potatoes, often those culled from sorting and processing operations, but sometimes from varieties bred especially for their starchcontent.

Potato starch won’t impart a starchy flavor to your finished product. It’s also a very refined starch with minimal protein or fat, a neutral taste, and a clear color. Like arrowroot, potato starch products have a very silky and glossyappearance.

Add it toward the end of cooking a sauce as well, since it doesn’t stand up well to long stovetop heating. It’s a great last-minute addition if your sauce is toothin.

Potato starch is used in soups, gravy, cakes, pastries, and pasta. It keeps very well for long periods of time. Store in an airtight container in a dark, dry, and cool place (no refrigeration isrequired).

Tapioca is refined from the cassava root (Manihot esculenta), which is cultivated globally in subtropical regions. Although it’s usually sold as “tapioca pearls,” turning it into a fine powder is easy in a spice grinder (or a second bowl of a coffeegrinder).

Tapioca thickens quickly, so it’s also a good choice for adjusting a too-thin sauce toward the very end of cooking;however, like other root starches, it doesn’t stand up well to long stovetopcooking.

Because it absorbs and thickens quickly, tapioca is a favorite for juicy pies and cobblers. It also stands up well to freezing andthawing.

ResistantStarches

You may have heard of another type of starch called“resistant starch.” As its name implies, resistant starch resists digestion in the stomach and small intestine. Resistant starch moves into the colon, where it feeds beneficial gut bacteria, conferring health benefits such as lower blood sugar levels, reduced appetite, and improved colonic function. Resistant starch is a complicated topic, worthy of a post or twoitself.

Maybe later, though. Berries are ripe. Time to make a cherry pie!