Is Ice Water the Key to Flaky, Tender Pie Crust?
And how does the temperature of H2O impact your pastry?
One of the prerequisites of working in the Martha Stewart test kitchen is being able to make a Martha-approved, flaky yet tender pie crust that looks as pretty as it is delicious. It's not a test of skill, but rather a test of your knowledge, as every great baker knows to follow a simple set of rules when making crusts. One non-negotiable is using ice cold water. If you aren't already chilling the water before making pie crust, doing so could be a total game changer.
At first glance it is very simple: combine three ingredients, flour, fat, and water (plus salt and sugar, if desired) and the result is a pie crust. However, the key lies in how the ingredients interact. Our Pie Crust 101 details all the steps to success, but not the why behind it. The two overarching themes are that the dough should be kept cold and the flour should not be overworked or over-hydrated. Ice water plays into both of these points.
Keeping the dough cold, starts with using cold, cubed fat, preferably butter. Lard and shortening both make fantastic crusts as well. Done properly, the unbaked crust should have small visible flakes of cold fat in it that create small air pockets during baking which is what creates a flaky crust. As the fat is mixed with the flour, it is warmed slightly. Then, the water is poured in, and the ice-cold temperature of the water prevents the fat from warming any further, which could potentially melt it into the flour rather than retaining the small bits of fat.
Over-hydrating the dough encourages gluten development, which is not desirable in pie crusts. Gluten formation toughens up the crust making it chewy rather than tender and flaky, which is what we want. Over-hydrated dough also has a tendency to shrink back when it is cooked. While not using too much water or over-processing the dough are the key tips here, the ice-cold temperature of the water also subtly plays into gluten formation. Flour does not absorb cold water as easily as warm water which helps keep the dough tender.
While it is easy to just use cold water straight from the faucet, the benefits of chilling the water with ice cubes outweigh that ease. Simply add water to a glass with ice cubes and let sit for a minute. Then measure out the water the recipe calls for, leaving the ice cubes behind. Any extra water in the glass is great for watering plants or hydrating yourself.