Preheat oven to 350 degrees and oil and flour a loaf pan.
In a large bowl, sift together the flours, baking powder, baking soda, salt and lemon zest. Set aside.
In a medium bowl, whisk together the egg, granulated sugar and Salute Santé! Grapeseed Oil until completely combined. Add apple sauce and lemon and grapefruit juice. Mix.
Pour the wet ingredients into the dry ingredients and mix until just combined. Transfer the batter to the 1prepared loaf pan.
Bake at 350 degrees for 45-50 minutes or until done. Do not over-bake. When done, remove from the baking pan immediately and cool completely on a wire rack.
Cool before adding the glaze.