There are two steps to creating an heirloom-quality fruit pie recipe. First, you’ll need to learn to create the perfect flaky pie crust. Once you’ve mastered the dough (or, found a store-bought pie crust that you love), the next step is creating a filling that’s firm enough to hold up on the end of your fork but not so thick that it turns into a pile of glue. The secret to the perfect pie filling is in the starch you choose, but how do you know which pie thickeners works best?
Starches have a beautiful ability to thicken sauces and give body your pie filling. While each thickener works in the same way–by bonding with water molecules and expanding–they all have unique characteristics. You can likely substitute one for another, but it all starts with understanding how each works and which will work best for your fruit pie.
Types of Pie Thickeners
Flour is a popular thickener for sauces and soups, and it can be used to add body to your fruit filling. It’s great because it thickens at low temperatures, but you’ll need to use more of it because it’s not as effective as some of the other starches. Most people prefer other thickeners over flour because it creates a cloudy filling with a slightly gummy texture and a wheat-flavored taste.
How to substitute: As a general rule of thumb, use twice as much flour as cornstarch or arrowroot.
Cornstarch is a super-effective thickener that doesn’t need much time to cook, although it does require high temperatures to activate. To avoid clumps, mix cornstarch with sugar before adding it to your filling.
When undercooked or used in excess, cornstarch can have a chalky taste and texture. Also, keep in mind that acidic ingredients (like lemon juice or vinegar) can weaken cornstarch’s ability to thicken, and it should never be used for pies you intend to freeze—it will turn spongy when thawed.
How much should you use: You’ll need half as much cornstarch as flour, but you can substitute cornstarch and arrowroot in equal parts.
Arrowroot is a great non-GMO substitute for cornstarch. Like cornstarch, it must be cooked at high temperatures, but it’s not weakened by acidic ingredients and it freezes exceptionally well. Avoid using arrowroot for cream-based pies, as it creates a slimy texture when combined with dairy.
How much should you use: Arrowroot can be substituted in equal parts as cornstarch.
Many people swear by quick-cooking tapioca as a pie thickener. This starch comes from the roots of the manioc or cassava plant and it’s sold as pre-gelatinized pearls. It requires low temperature for baking and has a neutral flavor, although it does give the filling a stippled texture that’s slightly gluey in texture, especially when overcooked. The tapioca also needs time to soften, so fillings mixed with tapioca must rest for at least 15 minutes before baking.
How much should you use: Tapioca can be substituted in equal parts as cornstarch or arrowroot.
Instant ClearJel is a pre-gelatinized, modified food starch derived from waxy maize. It can tolerate a range of temperatures (and can even thicken fruit without any heat at all). It’s used by many commercial bakeries because it works well with acidic ingredients, has a neutral flavor and creates clear, cloud-free fillings. Pies made with Instant ClearJel can also be frozen.
How much should you use: In general, Instant ClearJel can be substituted in equal parts as tapioca, cornstarch, or arrowroot.
If you’re wondering how much of each thickener to use, it really depends on the type of fruit you’re using. Fruits like apples are high in pectin (a naturally occurring thickener) and they don’t contain a lot of juice, so you won’t need much thickener for apple pies. On the other hand, fruits like berries are super juicy and release a lot of liquid as they cook. When combined with sugar, they release even more liquid, so berry pies require a decent amount of starch to thicken.
No matter what type of fruit you’re using, frozen fruit releases more juice than fresh fruit. When substituting frozen fruit, you’ll need 1/4 teaspoon more thickener per cup of filling.
We’ll leave you with one final note: Keep in mind that lattice-top fruit pies don’t need as much thickener because more moisture can evaporate as the pie bakes. If you’re making an open-topped pie, reduce your thickener by 1/4 teaspoon per cup of filling.
Now that you’re a pro, try baking up one of our favorite juicy fruit pie recipes!