Step 1: put the sugar and water into a pan and heat slowly until the sugar has dissolved. allow the syrup to cool.
Step 2: dissolve the gelatine in a little water and add with the undiluted orange juice to the sugar syrup. blend them together, then pour the liquid into a 1 pint shallow, plastic lidded container. put the sorbet in the freezer for half an hour or until barely firm.
Step 3: turn into a bowl and mash down until there are no large pieces. then fold in a stiffly whisked egg white. return to the container, cover and return to the freezer until required. thaw the sorbet in the refrigerator for 30 mins before serving. serves 4.