Could you experiment with a recipe like this? Substituting lemon peel for the lemon juice, etc. This is NOT the Panera recipe but it could give you a starting point.
Good luck and please share your results with us.

---

DEE'S HEALTH BREAD
Submitted by: Dee Dee
Yields: 72 servings

"Chock full of nutritious cracked wheat, sunflower and flax seeds, this robust whole-wheat bread has a wonderfully complex flavor."

2 tablespoons active dry yeast
1 teaspoon white sugar
1/2 cup warm water
3 1/2 cups warm water
1/4 cup honey
1/4 cup molasses
1/2 cup vegetable oil
2 eggs 2 tablespoons lemon juice
7 cups whole wheat flour
1/4 cup flax seed
1/4 cup cracked wheat
1/4 cup sunflower seeds
4 teaspoons salt
4 cups bread flour

1. In a small bowl, dissolve the yeast and sugar in 1/2 cup warm water. In a large bowl, mix remaining 3 1/2 cups warm water, honey, molasses, oil, eggs and lemon juice. Mix well. Add yeast mixture and stir.

2. Gradually add 5 cups whole wheat flour beating well after each addition. Add the flax, cracked wheat and sunflower seeds, stir well.

3. Let stand for 20 minutes, until mixture is very light. Stir in salt and the rest of the flours until dough pulls away from the sides of the bowl.

4. Knead 10 to 15 minutes until dough is smooth and elastic. Put into a greased bowl and cover, let rise in the oven with light on until doubled, about 1 hour.

5. Punch down and shape into 6 round balls. Cover and let rest for 20 minutes.

6. Form into loaves and let rise covered in oven until doubled. Bake at 375 degrees F (190 degrees C) 25-35 minutes.