Recipes engineered for perfection—what exactly does that mean? We take you inside Cook’s Illustrated’s science experiments.
While developing our recipe for baked apples, we couldn’t ignore a persistent problem: apples that “blew out” and collapsed in the oven. Could removing the skin solve the issue?
We prepared two batches of six baked Granny Smith apples each, one skin-on, the other skin-off, using our placeholder filling and sauce (raisins, toasted pecans, and brown sugar for the filling; apple cider for the sauce). Then we baked each batch in a 13- by 9-inch baking dish in a 375-degree oven until the apples could be pierced easily with a knife.
To our surprise, all the skin-off apples held their shape, without a single blowout. Within the skin-on batch, half of the apples collapsed.
In nature, the peel protects an apple; in the oven, it traps moisture that’s been transformed into steam. As the steam attempts to escape, its outward pressure ruptures cells and eventually bursts through the apple’s skin, causing blowouts. Removing all the skin allows the steam to escape without damaging the fruit’s structure.
MAKE IT NOW: Our recipe for Best Baked Apples is free through September 17, 2013.