Knife Skills: How to Cut Apples For Pies
Slicing a whole bunch of apples for a pie can be a chore, and those push-down-and-pop-out apple corer/slicer combos never seem to work right, producing fat wedges that don't sit right in the pie plate. If you're awesome with a paring knife, you can use the Jacques Pepin technique: twirl the knife around the top then the bottom, split it in half, cut out the seeds, and slice the wedges, all without ever letting the apple leave your hand. For the rest of us, here's the easiest, most consistent technique I've found.
It does produce a bit of waste around the very central core of the apple, but I feel that the time saved and convenience of the method is a reasonable trade-off. Plus I have a hamster I can feed those extra bits to.
Selecting an Apple
Different apples have different baking properties, and it mostly comes down to two factors: cell composition and acidity. The structure in the cell walls of apples comes from cellulose, while the individual cells are held together with pectin. Firm apples, like Granny Smith, Cortland, and Northern Spy contain plenty of cellulose, making them crisp to begin with, and helping them stay firm when cooked. Softer apples like McIntosh or Red Delicious are mealier to begin with, and turn to complete mush when cooked. Great for sauce, not so much for pie.
Acidity is also a factor. Pectin stays firmer in lower pH (I.E. more acidic) environments, so tart apples hold their shape better when cooked as well. More acidic apples also brown more slowly, so a good indication of how well an apple will perform in a pie is to let slices sit out and note how fast they brown. The ones that stay bright longest will generally work best in a pie.
For my taste, I find that if you're going for a single apple, the Golden Delicious has the best balance of sweetness, tartness, and good texture. It's my go-to for pies and tarts. Some people like to blend their apples to balance flavor and texture. Granny smith mixed with Cortland goes over pretty well for me as well.
Here's a tip: When pectin is heated to around 130°F, the pectin binding its cells converts to a more heat stable form. They'll stay firm and intact, even with subsequent cooking. If you gently parcook your apple slices in either a Dutch oven, or—even better—the microwave, you can get them to retain their shape throughout the entire baking process.