G'day Debbie, I do not know if this is the one you are after, but it sounds very very much like it. Enjoy. Angel.

Simple Citrus Sorbet

1 heaped tablespoon gelatine (unsweetened Jello)
1 1/2 cups cold water
1/2 cup boiling water
1 cup sugar
1 cup orange, lemon, grapefruit or lime fruit juice (or a combination)

Method
Sprinkle gelatine over 1/2 cup of the cold water in a medium pan. Stand for 10 minutes. Add the boiling water and stir over low heat until gelatine is dissolved.
Add sugar and stir without boiling until sugar is dissolved. Remove from heat.
Add remaining cold water, and the strained juice (juices) Refrigerate. Pour into freezer trays and freeze 2 to 3 hours or until just firm.
Scrape or scoop frozen mixture into chilled dessert dishes or wine glasses. May be garnished with small citrus leaves, shreds of citrus rind or mint sprigs.