7 Best Cornstartch Substitutes for Keto Desserts (and When to Use Them)

Cornstarch is a popular ingredient used to thicken puddings and custards and to improve the texture of baked goods. But it’s not exactly keto-friendly since it’s a type of carbohydrate with negligible amounts of fat and protein [1]. That means you’ll need a different thickener for your low-carb desserts. So, what exactly do you use? 

We’ve gathered around 7 of the best cornstarch substitutes used in keto desserts. Some are ideal for puddings, jams, and sauces, while others can help absorb excess liquid from pie fillings. But before you start using these swaps, it’s a good idea to learn about cornstarch and why it’s so often featured in desserts.

What Is Cornstarch?

Cornstarch is a thickener derived from the endosperm of corn kernels. It is a very fine, white powder with no smell or taste. It can absorb many times its weight in water when heated, which is a process known as starch gelatinization.

Sometimes called corn flour, cornstarch is used in both sweet and savory recipes. It can be used to thicken liquid ingredients or to create softer baked goods. 

Nutrition-wise, the name really says it all. Cornstarch is 90% starch, which is a complex carbohydrate that — although it raises blood glucose levels at a slower rate than glucose — still has a significant effect on it. Avoid cornstarch if you’re trying to keep blood sugar levels under check.

Why Do Dessert Recipes Often Call for Cornstarch as an Ingredient?

Cornstarch is a common ingredient in desserts. It is mainly used as a thickener for puddings, custards, fruit sauce, and pie fillings. You will also see it in bread and pastry because it helps create a melt-in-your-mouth texture and is also an anti-caking agent. 

In some recipes, cornstarch is used as a replacement for eggs thanks to its thickening and binding properties. It is also a frequent feature in gluten-free dessert-making since corn does not contain gluten. It can also be a substitute for cake flour in some recipes.  

7 Low-Carb and Keto-Friendly Alternatives to Cornstarch for Delicious Desserts 

Gelatin or agar-agar 

Gelatin, or its vegetarian alternative agar-agar, can be used to make low-carb pudding or berry sauce. Just check out this keto (and vegan) chocolate pudding or these mini cheesecakes as examples. It’s also a suitable alternative for low-carb jams and pie fillings. Working with gelatin can be tricky, however. You need to be careful not to use too much or too little or you’ll end up with soupy or stiff puddings and custards. A rule of thumb is to use 1 tablespoon of gelatin to 2 cups of water or 2 teaspoon of agar to every cup of liquid.

Chia seeds or flax meal

Chia seeds can absorb up to 15 times their weight in water and form a thick gel [2]. They’re often used as an egg replacer, but these tiny but mighty seeds also work as a cornstarch substitute in puddings, like this masala chai pudding. You can even add it to jams instead of pectin. Flax meal, on the other hand, has mucilage fiber, which is a thick and sticky substance that can work in place of corn starch in puddings and cookies [3].

Xanthan or Guar Gum

Both of these ingredients are polysaccharides added to food to help thicken or emulsify ingredients. They have no effect on blood glucose, thankfully, which is why they’re such a great cornstarch alternative for people on low-carb diets. You can use a small amount of both to make keto pudding or to improve the texture of pastry like in these Greek yogurt pancakes. 

Related: Keto Baking Essentials: Why Use Xanthan Gum?

Glucomannan Powder

Glucomannan powder is a natural fiber derived from the konjac plant, also known as elephant yam. It is the closest thing there is to cornstarch, with its white and powdery appearance and because it’s flavorless. It is also used like cornstarch — by first adding it to cold water to create sludge and then adding it to your recipe. Use Glucomannan powder to make puddings, custards, or cookies. 

Almond flour

Almond flour is already a popular cornstarch substitute in keto gravy and soups. It has a little bit of fiber and is able to absorb water to create a basic roux. You can also add it to pie fillings when you need something to absorb excess water or to thicken the ingredients. Substitute cornstarch with almond flour at a 1:1 ratio in any recipe and you’ll probably get similar results. 

Coconut flour

Of course, you can also substitute cornstarch with this popular keto flour as well. It can be used to thicken syrups, sauces, and fillings. But keep in mind that it has a distinctly coconut-y flavor that can take over your recipe if you’re not using spices or using mild-flavored ingredients. It’s also a good idea to use less coconut flour than you would other thickeners since it is highly absorbent. 

Wrapping Up: Key Takeaways from the Discussion on Cornstarch and Low-Carb Substitute

While you can’t use cornstarch on keto, there are plenty of fantastic substitutes to make your favorite desserts with. From gelatin and chia seeds to Glucomannan powder and nut flours, it’s easy to recreate creamy, silky, and thick textures when using the right ingredients and the correct methods. 

References: 

1. United States Department of Agriculture (USDA) Agricultural Research Service. FoodData Central. Cornstarch. April 2019. https://fdc.nal.usda.gov/fdc-app.html#/food-details/169698/nutrients

2. Ullah R, Nadeem M, Khalique A, et al. Nutritional and therapeutic perspectives of Chia (Salvia hispanica L.): a review. J Food Sci Technol. 2016;53(4):1750-1758. doi:10.1007/s13197-015-1967-0

3. Kaur M, Kaur R, Punia S. Characterization of mucilages extracted from different flaxseed (Linum usitatissiumum L.) cultivars: A heteropolysaccharide with desirable functional and rheological properties. Int J Biol Macromol. 2018;117:919-927. doi:10.1016/j.ijbiomac.2018.06.010