Rinse organic lemons with hot water and remove thin strips of zest with a vegetable peeler. In a saucepan, bring lemon zest, sugar and wine to a boil, stirring. Let stand 5 minutes on a warmer. Let cool and strain through a sieve. Squeeze juice from all of the lemons. Whip egg white until soft peaks form.
Stir lemon juice into wine mixture, then fold in egg white. Transfer mixture to an ice cream maker and process according to manufacturer's instructions. (Alternatively, pour mixture into a shallow metal bowl and freeze about 4 hours, stirring frequently with a fork to break up ice crystals.) With an ice cream scoop, scoop sorbet into small bowls. Garnish with lemon zest and lemon balm and serve immediately.