Smaller pieces of fruit will cook more quickly, but they also tend to lose more liquid since they have a higher surface-area-to-volume ratio.

For a truly fruit-packed pie, try slicing the apples flat instead of cutting them into wedges, and pat them down in the crust to make sure they lie flat, which minimizes collapse later.

Make sure to cut vents in the center of the top crust — those aren’t just to make the pie look pretty! Apples lose a third of their weight from evaporation and that steam needs a place to go to prevent your pie from swelling.

3. Sometimes the best pie is a day-old pie

Temperature is important for a nice pie texture.

Letting the pie cool isn’t just for preventing a burned mouth.

Because molecules flow more quickly past each other at higher temperatures, hot pie filling straight from the oven will be runnier.

Eating your pie the day after you bake it allows plenty of time for the pie to cool down and the filling to set.

As the pie cools, the pectin molecules of your fruit also spend more time interacting with each other. This results in a more solid, gel-like filling that will take longer to seep out of the pie when it’s cut and served on a plate.

A little bit of cornstarch, tapioca or flour can also help solidify the filling.

4. Types of flour

Different types of flour have different protein counts, based on the type of wheat the flour was made from.

Bread flour has a particularly high protein count. When mixed with water, it forms dense gluten networks that are great for chewy breads and bagels.

The gluten networks of a bagel

But for a flaky pie crust, you don’t want extensive gluten networks.

The gluten networks of a pie

Flours with lower protein content — such as pastry flour or cake flour — will create a less dense gluten network and a more tender crust. The challenge is that this type of flour can be more fragile to work with as a dough.

5. Booze

Have you ever added vodka to your apple pie? There’s a scientific reason for boozing up a pie crust.