Cornstarch, sometimes called cornflour, is the starch of corn. It is ground from the endosperm, or white heart, of the corn kernel. Cornstarch has a distinctive appearance and feel when mixed raw with liquids such as water or milk. Because it tends to form lumps, cornstarch is typically mixed with a small amount of cold liquid to create a thin paste before being stirred into a hot mixture. It is often included as an anti-caking agent in powdered and confectioner’s sugar. Recipes that use powdered sugar usually involve at least light cooking to eliminate the raw cornstarch taste.
Cornstarch thickens with a satiny smoothness and glossy appearance. It adds no flavor of its own, allowing the true taste of foods to shine through. Dishes thickened with cornstarch often have a brighter, more translucent appearance than those thickened with flour. Cornstarch also blends more easily with cold liquids than flour, as it doesn’t absorb liquid until it is heated.
Gluten is not present in cornstarch, making it an excellent substitute for flour in many recipes. This is particularly beneficial for individuals sensitive to gluten who require gluten-free food preparation. However, in baked goods like bread and cake, gluten plays a vital structural role, meaning flour or another gluten-containing ingredient is often necessary. Always check the recipe to determine whether cornstarch can be used as a substitute.
Cornstarch is commonly used as a thickening agent in puddings, sauces, and soups. Mixing it with a granular solid, such as granulated sugar, helps it disperse more evenly into a liquid. Sauces thickened with cornstarch are typically clear, unlike the opaque appearance of those thickened with flour. However, these sauces can thin out if cooked too long or stirred too vigorously. In many European cake and cookie recipes, cornstarch is combined with flour to create a finer-textured, more compact baked product.
Cornstarch is also frequently used to thicken gravies, glazes, soups, stews, casseroles, pies, and cake fillings. In cakes, cookies, and pastries, it is often mixed with flour to produce more tender results. Additionally, cornstarch is used to coat foods before frying and is a common ingredient in batters. Most packaged pudding mixes sold in supermarkets contain cornstarch, but homemade versions can be made using a double boiler. A basic cornstarch pudding typically consists of milk, sugar, cornstarch, and a flavoring agent.
Practical Uses and Substitutions for Cornstarch
Cornstarch has the same thickening power as arrowroot, potato starch, and tapioca, and can be substituted in equal amounts. It has twice the thickening power of flour, so only half as much is needed. The following conversion chart helps calculate the correct amount of cornstarch when substituting for flour:
Conversion Chart (Flour to Cornstarch)
| Flour | Cornstarch |
| If recipe calls for this much flour | Use this much cornstarch |
| 1 tablespoon | 1/2 tablespoon (1 ½ teaspoons) |
| 2 tablespoons | 1 tablespoon |
| 3 tablespoons | 1 1/2 tablespoons |
| 1/4 cup (4 tablespoons) | 2 tablespoons |
| 1/3 cup (5 1/3 tablespoons) | 2 tablespoons plus 2 teaspoons |
| 1/2 cup (8 tablespoons) | 1/4 cup (4 tablespoons) |
Cornstarch is especially effective in Asian cuisine. It enhances everything from plum dipping sauces to stir-fry mixes.
TIP: A stir-fry sauce mix can be frozen in tightly sealed containers in 3/4-cup portions for up to 3 months. Thaw and shake before use.
Beyond the kitchen, cornstarch is used in the manufacturing of environmentally friendly products. In 2004, Japanese company Pioneer announced a biodegradable Blu-ray disc made from cornstarch.
Other industrial and domestic uses of cornstarch include laundry starch, paper sizing, adhesive production, and cooking. Corn syrup and corn sugar are derived from the hydrolysis of cornstarch.
Cornstarch also has personal care applications. It’s an effective alternative to talcum powder, absorbing moisture efficiently. It can be found in powders, skin-cleansing milk, deodorants, and even as a remedy for sweaty shoes. For a skin cleanser, mix equal parts cornstarch and glycerin with one teaspoon of rum and a few drops of a preferred essential oil. Apply a small amount to your skin, massage gently, and rinse with warm water.
To absorb shine on oily skin, mix 1 tablespoon of cornstarch with kaolin (white clay) and dust it on the oily areas.
To combat sweaty feet, sprinkle a bit of cornstarch in your shoes before wearing them to help absorb moisture.
For a natural deodorant, combine cornstarch with finely ground lavender and pat under your arms to stay dry on hot days.
