Bring the sugar and water to the boil in a pan.
Remove the rind from the grapefruits and squeeze out all the juice.
Add the grapefruit juice to the syrup and boil for 10 minutes.
Leave this syrup to marinate overnight and then strain through a sieve. Place into an ice cream machine or into the deep freeze. If using a deep freeze, remove the mixture from time to time and stir.
© 1984 All rights reserved. Published by Jon Croft.