Prepare the Batter: Pour half of the lukewarm milk into a bowl, add yeast, and let it sit. In another bowl, mix the flour, pale ale, egg yolk, and a pinch of salt. After 10 minutes, add the rest of the milk with the yeast. Work in 2 tablespoons of peanut oil. Cover and leave at room temperature for 2 hours.
Prepare the Apples: Peel the apples and slice into rings. Optionally, use a melon baller to remove the core. Place apple rings into water with lemon juice.
Marinate the Apples: Drain the apples and mix with Calvados, lemon juice, and sugar. Let them sit for 30 minutes.
Whip Egg Whites: Take two egg whites and whip them until they hold peaks.
Fold in Egg Whites: Carefully fold the whipped egg whites into the bubbly batter.
Fry the Fritters: Dip the apple rings into the batter. Fry at 375°F (190°C) for about 90 seconds per side. Drain on paper towels.
Serve: Finish with a dusting of powdered sugar. Serve hot.