Put the sugar and water in a pan over heat to dissolve the sugar and then bring to the boil to make a syrup. Steep the zest in the syrup until cool.
When cool, mix with the champagne and lemon and orange juice and place in ice cream machine or deep freeze. If using a deep freeze, bring out from time to time and stir.
As the sorbet solidifies, add the whites beaten stiff with the sugar. This sorbet is at its best when freshly made.
© 1984 All rights reserved. Published by Jon Croft.