Dilute ½ cup salt and ½ cup sugar in 8 cups water. Pour into a bowl and place shrimps. Add more water if necessary. Refrigerate shrimps in water for approximately 3 hours.
Rinse quinoa under running water, rubbing with hands, until water comes clear. Drain and add to boiling water. Cook for 12 minutes. Drain and spread on a jelly roll pan until completely dry.
Place arrowroot with salt and egg whites in separate bowls. Remove shrimps from the refrigerator and dry.
Dredge each shrimp tail in arrowroot, shaking off the excess, dip into egg white and finally coat it with cooked and dried quinoa, pressing well to cover shrimp.
Place shrimps in an oven pan and refrigerate covered until ready to serve. Approximately, 20 minutes before serving heat oil until hot but not smoky (300°F/ 150°C). Fry shrimps for 3 minutes on both sides. Remove from oil and place over paper towels. Serve with Orange Syrup.
Orange and Honey Syrup:
Place all ingredients. In a medium saucepan and bring to a boil. Boil until slightly syrupy.
Season with salt and pepper. This sauce can be made 1 day ahead and kept in the refrigerator. Rewarm before using.