In a small saucepan heat oil to 350 D , using a thermometer to ensure proper temperature.
Meanwhile, whisk together egg whites and water until frothy in a small bowl. On a baking sheet, combine the flour and semolina and stir to blend. Dip thinly sliced zucchini into egg whites and then quickly into flour mixture, making sure to shake off excess before frying.
When oil reaches temperature, fry prepared zucchini rounds in three to four batches for three to four minutes, or until golden brown and crunchy. Drain on paper towel lined plate.
Sprinkle with salt and freshly ground black pepper to taste.