In a large bowl, dissolve yeast in warm water. Add sugar, oil, salt and 2 cups flour. Beat until blended. Stir in enough remaining flour to form a stiff dough., Turn onto a floured surface; knead until smooth and elastic, 6-8 minutes. Place in a greased bowl, turning once to grease top. Cover and let rise in a warm place until doubled, about 1 hour. Punch dough down; return to bowl. Cover and let rise for 30 minutes. , Preheat oven to 375°. Punch dough down. Turn onto a lightly floured surface. Shape into a 16x2-1/2-in. loaf with tapered ends. Sprinkle cornmeal over a greased baking sheet; place loaf on baking sheet. Cover and let rise until doubled, about 25 minutes. , Beat egg white and cold water; brush over dough. With a sharp knife, make diagonal slashes 2 in. apart across top of loaf. Bake until golden brown, 25-30 minutes. Remove from pan to a wire rack to cool.