A roux is a classic cooking technique used to thicken sauces, soups, and gravies. Traditionally, it’s made by cooking equal parts flour and fat (such as butter or oil) until smooth and thickened. But what if you’re avoiding flour due to dietary restrictions, gluten intolerance, or just want to try something new?
Luckily, there are several substitutes for flour in roux that work just as well. In this guide, we’ll explore the best alternatives, how to use them, and what to expect in terms of texture and flavor.
1. Why Use a Flour Substitute in Roux?
There are many reasons why you might need a replacement for flour in roux:
✔️ Gluten-free diets – Many people need a gluten-free roux for dietary or health reasons.
✔️ Low-carb and keto-friendly options – Some substitutes have fewer carbohydrates.
✔️ Different flavors and textures – Some flours or starches add a unique twist to your dish.
✔️ Allergy-friendly – Certain substitutes are better for those with wheat allergies.
Choosing the right alternative depends on what you’re making and your dietary needs.
2. Best Substitutes for Flour in Roux
1. Cornstarch
Cornstarch is a popular thickening agent that works well in place of flour. However, cornstarch isn’t cooked into a roux instead, it’s mixed with water to form a slurry and added at the end of cooking.
✔️ Gluten-free
✔️ Strong thickening power (use half the amount of flour)
✔️ Great for clear sauces and soups
How to Use:
-
Mix 1 tablespoon cornstarch with 2 tablespoons cold water before adding to a simmering sauce.
-
Stir continuously to avoid lumps.
2. Coconut Flour
Coconut flour is a great gluten-free and keto-friendly substitute, but it absorbs more liquid than regular flour, so adjustments are needed.
✔️ Mild coconut flavor
✔️ Low-carb option
✔️ Good for creamy dishes
How to Use:
-
Use ¼ the amount of coconut flour compared to regular flour.
-
You may need extra butter or liquid to balance absorption.
3. Almond Flour
Almond flour is another excellent low-carb and gluten-free choice, commonly used in keto recipes. It creates a slightly grainy texture but works well in creamy sauces.
✔️ Nutty flavor
✔️ Rich, buttery texture
✔️ Best for cheese-based sauces
How to Use:
-
Use 1:1 ratio as a flour replacement, but expect a slightly different consistency.
-
Works best in dishes like cheese sauces, gravy, and creamy soups.
4. Arrowroot Powder
Arrowroot powder is a neutral-flavored, gluten-free thickener that works similarly to cornstarch.
✔️ Odorless and tasteless
✔️ Gluten-free and paleo-friendly
✔️ Gives a smooth, glossy texture
How to Use:
-
Mix 1 tablespoon arrowroot powder with 2 tablespoons cold water before adding to a hot liquid.
-
Stir continuously to prevent clumping.
5. Rice Flour
Rice flour is a common thickening agent in Asian cuisine and is naturally gluten-free. It creates a smooth texture without altering flavor.
✔️ Mild taste
✔️ Works well for gravies and soups
✔️ Good substitute for traditional roux
How to Use:
-
Use 1:1 ratio when replacing wheat flour.
-
Cook slightly longer to remove any graininess.
6. Masa Harina
Masa harina is a corn-based flour often used in Latin American cooking. It gives sauces a slightly earthy, corn-like taste.
✔️ Great for Mexican-style dishes
✔️ Gluten-free and flavorful
✔️ Adds a rich, thick consistency
How to Use:
-
Use 1:1 ratio for flour replacement.
-
Works best in chili, enchilada sauce, or Tex-Mex gravies.
7. Potato Starch
Potato starch is another excellent gluten-free option that thickens sauces without changing flavor.
✔️ Smooth, creamy texture
✔️ Gluten-free and allergy-friendly
✔️ Best for delicate soups and sauces
How to Use:
-
Use ½ the amount compared to flour.
-
Dissolve in water before adding to hot liquid to avoid lumps.
8. Oat Flour
Oat flour is a good whole-grain alternative that provides a mild flavor and smooth texture.
✔️ Adds fiber and nutrition
✔️ Slightly sweet and mild taste
✔️ Works well in cream-based sauces
How to Use:
-
Use 1:1 ratio when replacing all-purpose flour.
-
Whisk well to prevent clumping.
3. How to Choose the Best Flour Substitute for Your Roux
The best alternative depends on your dish:
✅ For a gluten-free roux:Cornstarch, rice flour, potato starch, or arrowroot powder
✅ For a keto or low-carb roux:Coconut flour or almond flour
✅ For a classic thick, creamy texture:Rice flour or oat flour
✅ For a unique flavor:Masa harina or almond flour
Each substitute behaves slightly differently, so adjustments may be needed.
4. Tips for Making a Roux Without Flour
✔️ Cook the substitute in fat first – Just like a traditional roux, cook it with butter or oil for better texture.
✔️ Adjust the liquid – Some flours absorb more liquid, so you may need to add extra broth or milk.
✔️ Use low heat – Some alternatives thicken faster than regular flour and can burn quickly.
✔️ Whisk constantly – To prevent lumps, stir continuously while cooking.
Replacing flour in roux is easy with the right substitute. Whether you’re looking for a gluten-free, low-carb, or unique alternative, there are plenty of options to choose from. Experiment with different substitutes to find the perfect match for your favorite dishes!