Can you use cornstarch in place of xanthan gum?

October 21, 2025 •

4 min read

Over 60% of US households have cornstarch, but far fewer stock xanthan gum, leading many home cooks to wonder: Can you use cornstarch in place of xanthan gum? The short answer is yes, but the effectiveness depends heavily on the recipe's purpose, as these two ingredients function differently despite both being used for thickening.

Quick Summary

Cornstarch can replace xanthan gum for thickening sauces and gravies, but it is not a suitable substitute for binding in most gluten-free baking due to functional differences that affect final texture.

Key Points

Not a Direct Substitute: Cornstarch cannot universally replace xanthan gum due to different chemical properties and activation methods.
Good for Thickening Hot Liquids: Cornstarch is a reliable and affordable thickener for hot sauces and gravies, requiring heat to activate.
Poor for Gluten-Free Baking: Cornstarch lacks the binding and emulsifying properties of xanthan gum, resulting in dense or crumbly gluten-free baked goods.
Requires a Slurry: Always mix cornstarch with a cold liquid first to create a slurry before adding it to a hot recipe to prevent clumping.
Explore Alternatives: For gluten-free baking, consider using better substitutes like psyllium husk or guar gum, which provide the necessary binding and elasticity.
Texture Differences: Cornstarch creates a smooth, glossy texture, while xanthan gum is known for its elastic and gelatinous qualities.
Consider the Recipe: Evaluate whether your recipe needs a simple thickener (cornstarch) or a more complex binder and stabilizer (xanthan gum) before substituting.

The Fundamental Difference in How They Work

While both cornstarch and xanthan gum are used as thickeners, their chemical makeup and activation methods are distinct. Understanding these differences is key to successful substitution.

Xanthan gum is a polysaccharide produced by the fermentation of sugar by the bacterium Xanthomonas campestris. Its molecular structure allows it to create a gel-like substance that functions as a powerful stabilizer and emulsifier, preventing ingredients from separating. Importantly, it doesn't need heat to activate and can even thicken cold liquids, making it ideal for salad dressings, smoothies, and gluten-free recipes that require structure.

Cornstarch is a carbohydrate derived from the endosperm of corn kernels. Unlike xanthan gum, it must be heated to swell and thicken liquids. It does not provide the same binding or emulsifying properties. It creates a smooth, translucent consistency in sauces but fails to replicate the elasticity and crumb structure that xanthan gum provides in gluten-free baking.

When Cornstarch Can Be an Effective Substitute

For certain applications, cornstarch is a perfectly acceptable replacement for xanthan gum, particularly when the goal is simple thickening in a heated liquid. This is where cornstarch truly shines as an affordable and readily available option.

Sauces and Gravies: When thickening a hot liquid, a cornstarch slurry is a reliable solution. The process involves mixing cornstarch with an equal amount of cold water to form a smooth paste before whisking it into the simmering liquid. This prevents clumping and allows the starch granules to swell and thicken evenly. If the recipe originally called for xanthan gum for thickening a hot sauce, you can often use a larger amount of cornstarch. A general starting ratio is 1 tablespoon of cornstarch for every 1/2 to 1 teaspoon of xanthan gum.

Custards and Puddings: Cornstarch is the traditional ingredient for thickening custards and puddings. Its activation with heat creates the creamy, smooth texture that is characteristic of these desserts. If a recipe uses xanthan gum for thickening this type of cooked dessert, cornstarch can be used, though the amount may need adjusting.

Using a Cornstarch Slurry:

Mix 1 part cornstarch with 1 part cold liquid (usually water) until a smooth paste forms. This is the slurry.
Slowly whisk the slurry into your hot liquid, and bring the mixture to a boil. Cornstarch will not fully thicken until it reaches boiling temperature.
Stir constantly as it heats to prevent lumps and scorching. Cook for a minute or two after boiling to remove any raw, starchy flavor.

Why Cornstarch Fails in Gluten-Free Baking

This is where the substitution falls apart. For those on a gluten-free diet, xanthan gum is a crucial ingredient that provides the elasticity and binding power that gluten would normally offer. Replacing it with cornstarch will not yield the same results.

Lack of Binding: Xanthan gum creates a network that holds gluten-free dough together, preventing a dry, crumbly texture. Cornstarch acts as a tenderizer by absorbing moisture but does not form the necessary elastic structure.
Different Texture: While cornstarch can make gluten-free goods lighter and more tender by replacing some heavier flours, it will not create the chewy, cohesive texture that xanthan gum is known for in breads and baked goods.
Overly Moist or Dry Results: Without xanthan gum's moisture-retaining and emulsifying properties, gluten-free baked goods can end up too moist and dense or crumble apart entirely.

Comparison: Xanthan Gum vs. Cornstarch


Feature	Xanthan Gum	Cornstarch
Function	Thickener, emulsifier, stabilizer, and binder.	Thickener, moisture absorber.
Activation	No heat required; works in hot or cold liquids.	Requires heat to thicken.
Usage	Effective in small amounts due to potency.	Requires more volume for thickening.
Texture	Can be slightly slimy or gelatinous if overused; provides elasticity in baked goods.	Smooth and glossy when properly cooked; can feel grainy if undercooked.
Best For	Dressings, sauces, smoothies, gluten-free baking.	Sauces, gravies, custards, puddings.
Stability	Stable across wide temperature and pH ranges, freezable.	Breaks down with extended heating, freezing, or high acidity.

Other, Better Substitutes for Xanthan Gum

If you're in a gluten-free baking scenario, it's best to look beyond cornstarch for an effective replacement. Several other options mimic xanthan gum's properties much more closely.

Psyllium Husk: A soluble fiber that forms a gel when mixed with water. It is an excellent binder, especially for yeasted gluten-free breads, providing structure and elasticity. Use approximately twice the amount of psyllium husk powder for the amount of xanthan gum called for.

Guar Gum: Derived from guar beans, this is another polysaccharide used as a binder and thickener. It works well in cold applications and can be a good replacement, though it doesn't retain moisture as effectively as xanthan gum in higher-temperature baking. Use about 2.5 times the amount of guar gum as xanthan gum.

Chia or Flax Seeds: When mixed with water, ground chia or flax seeds form a thick, gel-like substance that can be used as a binder in baking. They add a nutty flavor and some grittiness, so they are not ideal for all applications. Use a 1:1 ratio with water to form the gel.

Conclusion

While cornstarch is a cheap and effective thickener for hot sauces, gravies, and custards, it is not a suitable substitute for xanthan gum in most gluten-free baking. The two ingredients have fundamentally different functions and activation methods. Cornstarch lacks the binding and emulsifying properties that make xanthan gum so valuable for creating structure in gluten-free goods. For successful substitutions in baking, explore alternatives like psyllium husk or guar gum that more closely replicate xanthan gum's gluten-like functionality. Understanding the science behind these ingredients is the key to preventing kitchen disasters and achieving your desired culinary results.

For more detailed information on xanthan gum and its uses, the Healthline article on substitutes is a helpful resource.

Frequently Asked Questions

The main difference is their function and activation. Xanthan gum acts as a binder and emulsifier, creating elasticity in baked goods and thickening cold liquids without heat. Cornstarch is purely a thickener that requires heat to activate and does not provide binding or emulsification.

No, cornstarch is a poor substitute for xanthan gum in gluten-free bread. Xanthan gum provides the binding and elasticity that mimics gluten, which cornstarch cannot. Using cornstarch will likely result in a crumbly, dense loaf.

For a hot sauce, start by using approximately 1 tablespoon of cornstarch (mixed into a slurry with cold water) for every 1/2 to 1 teaspoon of xanthan gum the recipe calls for. Remember that cornstarch must be heated to thicken effectively.

No, cornstarch requires heat to activate and thicken. For cold liquids like salad dressings or smoothies, xanthan gum is the correct choice because it thickens without needing high temperatures.

Using too much xanthan gum can result in a slimy, rubbery, or gummy texture in your food. It is a potent thickener, so a little goes a long way. This effect is more common with xanthan gum than with cornstarch.

Better substitutes include psyllium husk powder, guar gum, and ground chia or flax seeds. These ingredients have binding properties that more effectively replicate the role of gluten than cornstarch does.

Yes, cornstarch is naturally gluten-free. However, if you have celiac disease, you should always check the product label to ensure it is certified gluten-free and has not been processed in a facility with cross-contamination risk.