Preheat the oven to 350-degrees. Lightly spray a 13"x9"x2" baking pan with no-stick spray. Set pan aside.

In a small saucepan, bring the pineapple juice to a boil. Then reduce the heat. Simmer, uncovered, until the juice has reduced to 1/2 cup. Set the juice aside.

In a large bowl, beat the egg whites until foamy. Stir in the applesauce. Then stir in the cake mix, gelatin and lemon peel.

Slowly drizzle the pineapple juice into the batter. Using an electric mixer, beat the mixture on medium speed for 5 minutes. Spread the batter in the prepared pan. Bake for 30 to 40 minutes or until the cake springs back when lightly touched in the center.

Meanwhile, in a small bowl, stir together the powdered sugar and lemon juice until smooth.

Remove the cake from the oven. Use a toothpick to poke holes in the top of the cake, then pour the lemon juice mixture over the hot cake. Cool the cake before serving.