Ingredients
Method
1.Stir rind, sugar and the water in medium saucepan over high heat until sugar dissolves; bring to the boil. Reduce heat; simmer, without stirring, uncovered, 5 minutes. Transfer to large heatproof jug, cool to room temperature. Stir in juice.
2.Pour sorbet mixture into loaf pan; cover tightly with foil. Freeze 3 hours or overnight.
3.Process sorbet mixture with egg white until smooth. Return to loaf pan. Cover; freeze until firm. Serve with extra grapefruit rind, if you like.