Bring the rhubarb juice, sugar and lemon zest to the boil briefly while stirring. Leave to cool. Beat egg white until stiff. Mix cooled rhubarb juice, lemon juice and beaten egg whites. Pour into a bowl and let it freeze for about 90 minutes.
Stir well and freeze for another 30 minutes. Then form into small balls with the scoop and freeze for another 30 minutes. In the meantime wash, clean and quarter the strawberries. Sprinkle with strawberry liqueur and leave to stand. Serve the sorbet balls and strawberries in portions, each decorated with a delicate rhubarb stick
With 6 people: