Remove the ends of the eggplant, slice the eggplant lengthwise on a mandolin into 1/8-inch thick strips, discard the pieces with excess skin, slice the strips into 1-inch wide pieces and trim off the skin.
Mix together the flour, soda water, and salt.
Dredge the eggplant slices in the batter, then fry in hot oil, turning once, until golden on both sides.