1. Place the breadcrumbs in a small bowl.
2. Mix the dry mustard into the breadcrumbs.
3. In another bowl beat the egg white and the milk together well.
4. Dip each fish fillet into the egg mixture.
5. Roll in the breadcrumbs to cover the fish completely.
6. Place fillet on a cookie sheet.
7. Preheat the oven to 425 degrees.
8. Cook the fish 15 minutes.
9. Fish is done when the fish flakes easily with a fork.
10. Serve with the lemon wedges.