Soak gelatine in a bowl with cold water. Crushed melon puree. Beat cream, yogurt and powdered sugar. Add puree melon. The softened gelatin is melted over low heat with the juice of an orange, then added a little to the prepared cream. Beat well egg whites and also very gently added to the cream. This reconstituted dessert put in optional form and keep a few hours in the refrigerator. Before serving him removed from the mold and put in an appropriate dish.