Put the egg white in a fat-free mixing bowl. Beat with the whisks of the hand mixer until stiff. Gradually add sugar and lemon juice while stirring and continue beating until the sugar has dissolved.
Carefully fold in the grated coconut. Spread the wafers on a baking tray. Place heaps on the wafers with two teaspoons. Bake in a preheated oven (electric: 150°C/ gas: level 1) for 30-35 minutes.
Let it cool down well on a cake rack. Makes about 18 macaroons.